Friday, February 27, 2015

Internal audit slams DHS for canceling technology to fight bio-threats/ WaPo

And another story about an inexplicable contracting decision regarding a biodefense product, in today's WaPo:
Last year, a Silicon Valley start-up came close to producing what government scientists considered a breakthrough technology — a device the size of a ski boot that could test for tiny microorganisms at rapid speed, helping to safeguard the nation from bio-threats.
But six months before the firm, NVS Technologies, was to deliver its first prototypes, the Department of Homeland Security suddenly canceled its contract. According to a draft audit report and government scientists familiar with the project, the decision was improperly made by a single agency official, without supporting evidence and over the objections of numerous experts within DHS’s Science and Technology Directorate.
The directorate’s own review had cited “substantial data” showing that the new technology worked and was needed to help detect bio-threats, said the audit by the DHS inspector general’s office. The report, dated Nov. 26, has not been finalized but is expected to be made public soon, government officials said...

Monday, February 23, 2015

Limited airborne transmission of Ebola is ‘very likely,’ new analysis says/ WaPo

As discussed in this blog last October and November, Ebola transmission by air is likely, but also likely not a major form of spread. The WaPo comments on an academic piece written by several experts in the field:
... As evidence, the research notes that Ebola virus has been found on the outside of face masks worn by health workers caring for victims of the disease. It also points out that the virus has been passed between animals via respiration. And the authors say that Ebola can infect certain cells of the respiratory tract, including epithelial cells, which line body cavities, and macrophages, a type of white blood cell that consumes pathogens.
The paper notes that breathing, sneezing, coughing and talking can release droplets of fluid from the respiratory tract that travel short distances and most likely cause infection by settling on a mucous membrane. Those actions also release smaller airborne particles capable of suspension in mid-air that can be inhaled by others. Technically, both qualify as aerosols, the paper says.
The debate has centered on whether Ebola can be transmitted via those smaller particles. William Schaffner, an infectious disease specialist at Vanderbilt Medical Center who did not take part in the study, praised it for raising the issues "in a thoughtful fashion" and predicted it would be "very, very widely read."
He said he could imagine the possibility of respiratory transmission of Ebola from close-in contact, perhaps a distance of three or four feet. Even so, Schaffner said, it would be rare; as the study points out, it has never been demonstrated in humans.
The common mode of transmission--contact with body fluids--"those are the highways of transmission," Schaffner said. "Could respiratory transmission occur? Yes. But it's probably a byway, a little trail in the forest."
Asked why many more people who were near Ebola victims had not become infected, Osterholm said the Ebola virus may be much less contagious than other diseases spread by respiration, such as measles. He likened it to tuberculosis, which is more difficult to contract this way.
In an e-mail, Kobinger said that "we hope that this review will stimulate interest and motivate more support and more scientists to join in and help address gaps in our knowledge on transmission of Ebola (and other filoviruses). Important policies and biosafety regulations must be evidence-based, not [by] using opinions and beliefs as guiding principles."
The review itself points out that "to date, investigators have not identified respiratory spread (either via large droplets or small-particle aerosols) of Ebola viruses among humans. This could be because such transmission does not occur or because such transmission has not been recognized, since the number of studies that have carefully examined transmission patterns is small."

Wednesday, February 18, 2015

FACTS: Only 25% of recent US measles cases were vaccine refusers; there have been no US measles deaths since 2003; most of those with measles have been adults/ CDC

A few facts about measles need to be told.  Measles is not rapidly expanding in the US or internationally, and CDC says the rate of vaccination for measles has been stable since 1994. (However, in some states, like Oregon, the number of vaccine waivers has tripled to 6% in about 10 years.  In response, last March Oregon tightened its rules for vaccine exemptions, requiring parents to be educated about vaccines before refusing.) The following comes exclusively from the CDC and WHO.

1.  No one has died in the US from an acute case of measles since 2003.  Because Snopes claimed this was a lie, I checked with the measles experts at CDC, who wrote me the following email today:
"Good Afternoon,
Thank you for your inquiry regarding measles deaths.  Measles data available to the public can be found in www.cdc.gov/measles, MMWR (http://www.cdc.gov/mmwr/), and other publications such as those listed on http://www.cdc.gov/measles/resources/ref-res.html.
The last documented deaths in the US directly attributable to acute measles occurred in 2003.  Before the measles vaccination program started in 1963, we estimate that 3-4 million people got measles each year in the US, and 400-500 of those died (http://www.cdc.gov/measles/about/faqs.html). 
 Kind Regards,
Division of Viral Diseases
Centers for Disease Control and Prevention"
2.  Worldwide, according to the WHO, measles deaths were reduced by 74% between 2001 and 2010.

The majority of measles deaths occurred in India and Africa where not enough children are being vaccinated. India accounted for 47% of all measles deaths, followed by the entire African region at 36%... 

“This is still a huge success,” study author Peter Strebel, a measles expert at WHO, told the AP. Strebel said the 85% vaccination coverage rate is the highest ever recorded. 


4.  Over half the cases have occurred in adults.  The median age of recent measles cases is 22.

"As of February 11, a total of 125 measles cases with rash occurring during December 28, 2014–February 8, 2015, had been confirmed in U.S. residents connected with this outbreak. Of these, 110 patients were California residents. Thirty-nine (35%) of the California patients visited one or both of the two Disney theme parks during December 17–20, where they are thought to have been exposed to measles, 37 have an unknown exposure source (34%), and 34 (31%) are secondary cases. Among the 34 secondary cases, 26 were household or close contacts, and eight were exposed in a community setting. Five (5%) of the California patients reported being in one or both of the two Disney theme parks during their exposure period outside of December 17–20, but their source of infection is unknown. In addition, 15 cases linked to the two Disney theme parks have been reported in seven other states: Arizona (seven), Colorado (one), Nebraska (one), Oregon (one), Utah (three), and Washington (two), as well as linked cases reported in two neighboring countries, Mexico (one) and Canada (10).
Among the 110 California patients, 49 (45%) were unvaccinated; five (5%) had 1 dose of measles-containing vaccine, seven (6%) had 2 doses, one (1%) had 3 doses, 47 (43%) had unknown or undocumented vaccination status, and one (1%) had immunoglobulin G seropositivity documented, which indicates prior vaccination or measles infection at an undetermined time. Twelve of the unvaccinated patients were infants too young to be vaccinated. Among the 37 remaining vaccine-eligible patients, 28 (67%) were intentionally unvaccinated because of personal beliefs, and one was on an alternative plan for vaccination. Among the 28 intentionally unvaccinated patients, 18 were children and ten were adults...

Sunday, February 8, 2015

Safety and Effectiveness of the MMR vaccine: info from CDC and DHHS

I've been asked to contrast the risk from the disease measles with the risk from the measles vaccine, usually the MMR.  MMR stands for Measles, Mumps, Rubella (rubella is german measles) and so the MMR vaccine contains 3 live, attenuated (weakened) viruses that reproduce in the body of the person receiving the vaccine. Live vaccines usually provide a stronger immune response than a killed vaccine, which does not reproduce in the body after being injected. However, there are risks from vaccination, and some MMR vaccine recipients develop symptoms from mild forms of the three diseases. Note that the MMR-V, a newer vaccine, has varicella (chickenpox) added to the MMR components, and is associated with a higher rate of adverse event reporting and federal vaccine injury compensation than MMR.

Many of the vaccine side effects are also side effects of the disease.  They generally occur more frequently from the disease than the vaccine.  But because virtually every child gets the vaccine, while only one in 100,000 will get measles in their lifetime, children are more likely to suffer a severe side effect from the vaccine than the disease, in the US.
  
The Rubella virus component can cause joint pain in up to 25% of women. The Mumps component can cause swollen glands in 1 in 75 recipients. One in 3,000 recipients will have a seizure. One in 30,000 develops ITP (Idiopathic Thrombocytopenic Purpura) due to the measles component, in which autoimmune destruction of platelets occurs that can be life-threatening. There is a ten-fold increase in incidence of ITP during the 6 weeks following vaccination. 

Rarely, there may be lasting seizures, deafness, coma or brain damage, and deaths post-vaccination. These illnesses are termed, for purposes of federal compensation, encephalitis or encephalopathy.


Below are listed the warnings in CDC's MMR Vaccine Information Statement:

What are the risks from MMR vaccine?

  • A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions.
  • The risk of MMR vaccine causing serious harm, or death, is extremely small.
  • Getting MMR vaccine is much safer than getting measles, mumps or rubella.
  • Most people who get MMR vaccine do not have any serious problems with it.

Mild problems

  • Fever (up to 1 person out of 6)
  • Mild rash (about 1 person out of 20)
  • Swelling of glands in the cheeks or neck (about 1 person out of 75)
If these problems occur, it is usually within 6-14 days after the shot. They occur less often after the second dose.

Moderate problems

  • Seizure (jerking or staring) caused by fever (about 1 out of 3,000 doses)
  • Temporary pain and stiffness in the joints, mostly in teenage or adult women (up to 1 out of 4)
  • Temporary low platelet count, which can cause a bleeding disorder (about 1 out of 30,000 doses)

Severe problems (very rare)

  • Serious allergic reaction (less than 1 out of a million doses)
  • Several other severe problems have been reported after a child gets MMR vaccine, including:
    • Deafness
    • Long-term seizures, coma, or lowered consciousness
    • Permanent brain damage
These are so rare that it is hard to tell whether they are caused by the vaccine.

Below are the side effects, following use of a Measles or Rubella-containing vaccine, that the US government has acknowledged are due to these vaccines, for which it will pay compensation through the Vaccine Injury Program.  This official list is termed the Vaccine Injury Table


It lists the vaccine, the serious side effect, and the period following a vaccination during which it would be expected to occur. Note that although the CDC said that joint pains are temporary, they can be be chronic, and a reason for compensation, in some recipients of MMR (usually females):



III. Measles, mumps, and rubella vaccine or any of its components (e.g., MMR, MR, M, R)
A. Anaphylaxis or anaphylactic shock
4 hours.
   
B. Encephalopathy (or encephalitis)
5-15 days (not less than 5 days and not more than 15 days).
   
C. Any acute complication or sequela (including death) of an illness, disability, injury, or condition referred to above which illness, disability, injury, or condition arose within the time period prescribed
Not applicable.
IV. Vaccines containing rubella virus (e.g., MMR, MR, R)
A. Chronic arthritis
7-42 days.
   
B. Any acute complication or sequela (including death) of an illness, disability, injury, or condition referred to above which illness, disability, injury, or condition arose within the time period prescribed
Not applicable.
V. Vaccines containing measles virus (e.g., MMR, MR, M)
A. Thrombocytopenic purpura
7-30 days.
   
B. Vaccine-Strain Measles Viral Infection in an immunodeficient recipient
6 months.

The federal Vaccine Injury Compensation Program began in 1988. Through March 2014, 967 claims had been made to the program for vaccines against measles. These claims included 58 deaths.

Compensation was granted to the families of 376 claimants. Compensation was denied to 504 claimants, and 87 cases were still pending in March 2014.

Thousands of reports to the joint FDA-CDC Vaccine Adverse Event Reporting System have been made regarding adverse effects that occurred in close proximity to an MMR or MMR-V inoculation, including several hundred reports of deaths.  However, there is no systematic review of most of these reports, and no determination is made as to whether the vaccine caused the reaction, in the vast majority of cases.

Herd immunity is working. Protection against measles was estimated by CDC at 93% after one dose of MMR and 97% after a second MMR. Most vaccinated children are posed no harm by an exposure to measles.  It is primarily the unvaccinated who are at risk. But the risk of a serious sequela from measles is small, and as I noted in my last blog post, using CDC's numbers, I can only find one child who has died in the US from measles during the past 12 years.  

The chance of being exposed to measles in the US today is less than the chance of having an adverse reaction to a measles vaccine. But measles is an unpleasant illness. Being unvaccinated or being vaccinated--well, each choice poses its own risks.

Luckily, we have some choice whether to vaccinate or not. Or to delay vaccination. Life is never risk-free. But in this case, you may choose your risk. 

* Snopes claims that it is a lie that no one has died from measles in the US in the past ten years. 

UPDATE Feb. 18:  I contacted CDC to resolve the contradictions in their data. The Division of Viral Illnesses at CDC responded today, and confirmed that the last death in the United States from acute measles occurred in 2003. Snopes is wrong, and I have asked Snopes to correct their post.

UPDATE Feb.22: Snopes failed to change their website despite receiving a copy of the CDC memo affirming that the last US measles death was in 2003. I must presume Snopes is not as interested in promoting the truth as it claims.

Snopes says there were 2 measles deaths in 2009 and 2 in 2010, citing National Vital Statistics Reports for 2009 and 2010.  However, CDC said here that 2 deaths from measles occurred in 2003, not 2009. CDC's measles experts further say there were only 2 deaths between 2001 and 2011:

From 2001 through 2011, a median of 63 measles cases (range: 37–220) and four outbreaks, defined as three or more cases linked in time or place (range: 2–17), were reported each year in the United States. Of the 911 cases, a total of 372 (41%) cases were importations, 804 (88%) were associated with importations, and 225 (25%) involved hospitalization. Two deaths were reported.
There have been no reported measles deaths since 2011. Therefore, as best I can tell, there have been only 3 US measles deaths since 1993. Because two government databases provide contradictory information as to when those deaths occurred, and how many occurred, Snopes might be right, or my claim of none since 2003 may be right.  But the CDC measles experts should be more likely to know the correct numbers than those providing US mortality data for all causes. Here are my additional sources:

Orenstein in 2004 noted that deaths had declined to zero from measles"Annual US measles deaths have declined from 408 in 1962 to 0 from 1993-present [213]." According to the National Immunization Program"No measles deaths were reported to NIP during 1993–2001." Hinman noted in 2004: "During 1993–1999, only 1 acute measles-related death was reported to the NCHS and no deaths were reported to the NIP. This is consistent with the extremely low reported incidence of measles in the United States during these years."  Clearly, there have been only a small number of deaths from measles since 1993.

According to CDC, before the MMR vaccine, in the 1950s, there were an estimated 3-4 million cases of measles in the US yearly, and an average 440 deaths: one death in about 7-10,000 cases. About 1 in 4,000 cases developed permanent brain damage from measles

These data are consistent with what I previously found.  Pundits who keep claiming that measles kills one in 1,000 affected children, which was no longer true by the 1950s, haven't bothered to check the facts. (I have heard about the 1/1000 deaths from measles for decades--it is a persistent urban myth that may have hung on due to the dearth of mortality data in recent decades.
So few children die from measles in the US, we cannot reliably calculate a case fatality rate.  

How effective is the MMR vaccine and how long does protection last? It depends on the study. Duration seems to be at least 15 years, but it does drop over time. Delaying a child's first vaccination from the currently recommended 12-15 months (or age 6 months for foreign travel) makes the vaccine more likely to be effective. That is one reason I would delay, especially if there was a small risk of exposure and the child was otherwise healthy. 

Here is what CDC had to say in 2013 about the effectiveness and duration of protection of measles vaccines:
Measles Vaccine Effectiveness
One dose of measles-containing vaccine administered at age ≥12 months was approximately 94% effective in preventing measles (range: 39%–98%) in studies conducted in the WHO Region of the Americas (141,142). Measles outbreaks among populations that have received 2 doses of measles-containing vaccine are uncommon. The effectiveness of 2 doses of measles-containing vaccine was ≥99% in two studies conducted in the United States and 67%, 85%–≥94%, and 100% in three studies in Canada (142146). The range in 2-dose vaccine effectiveness in the Canadian studies can be attributed to extremely small numbers (i.e., in the study with a 2-dose vaccine effectiveness of 67%, one 2-dose vaccinated person with measles and one unvaccinated person with measles were reported [145]). This range of effectiveness also can be attributed to age at vaccination (i.e., the 85% vaccine effectiveness represented children vaccinated at age 12 months, whereas the ≥94% vaccine effectiveness represented children vaccinated at age ≥15 months [146]). Furthermore, two studies found the incremental effectiveness of 2 doses was 89% and 94%, compared with 1 dose of measles-containing vaccine (145,147). Similar estimates of vaccine effectiveness have been reported from Australia and Europe (Table 1) (141). 
     Duration of Measles Immunity after Vaccination
Both serologic and epidemiologic evidence indicate that measles-containing vaccines induce long lasting immunity in most persons (148). Approximately 95% of vaccinated persons examined 11 years after initial vaccination and 15 years after the second dose of MMR (containing the Enders-Edmonston strain) vaccine had detectable antibodies to measles (149152). In one study among 25 age-appropriately vaccinated children aged 4 through 6 years who had both low-level neutralizing antibodies and specific IgG antibodies by EIA before revaccination with MMR vaccine, 21 (84%) developed an anamnestic immune response upon revaccination; none developed IgM antibodies, indicating some level of immunity persisted (153).

Thursday, February 5, 2015

What you need to know about the measles epidemic. Then relax



Measles is uncomfortable. I remember having it, and it was the worst of all my childhood diseases. It was very painful to eat and drink. Still, I was better in about a week. And then I had life-long immunity.  

What is the death rate from measles? 

By the time I had measles, in 1959, only one in 10,000 children died from it.  See the following graph from a 1972 paper, which demonstrates that by 1945, there were minimal fatalities from measles. 


There is confusion about this. It is widely claimed that one in one thousand children with measles will die. Back in the 1950s and early '60s, about 500,000 measles cases were reported yearly, and there were an average 440 deaths.  But about 4 million cases occurred yearly in the US, while most were not reported to authorities. Unlike today, there was no requirement to report cases of measles, nor did parents feel every child with measles needed to see a doctor. When only reported cases are considered, there is one death per thousand cases. But when all cases are considered, there was only 1 death in 10,000 cases of measles. However, in developing countries, where malnutrition is common and dehydration may go untreated, the death rate is considerably higher.


In 1945, penicillin was only starting to be available, and modern ICUs and ventilators did not yet exist. Instead, simple care with adequate hydration kept people alive until they got over it. This is the usual therapeutic approach to viral illnesses. Here's the proof that it works, from Measles death:case ratios, New York State,1910–1969, by decade. Reprinted from Hinman ARResurgence of measles in New YorkAm J Public Health 1972;62:498-503.

Figure 2.
























Vaccine refusers are a minority of those susceptible to measles

You might be surprised to learn that vaccine refusal plays a relatively small part in the number of measles-susceptible people in the US. CDC data show the median rate of non-medical vaccine waivers in US schoolchildren was only 1.7% last year. This is less than 1.5 million children.


There are 3 other categories of children and adults who are susceptible to measles, but who are not considered vaccine refusers.  Even if every child with a non-medical vaccine waiver was required to get the MMR (measles, mumps, rubella) vaccine on time, there would still be 6-7% of Americans who could catch measles if exposed:
  • People who have survived childhood cancers, organ transplants and HIV infections, or been treated for serious autoimmune diseases, usually avoid the (live) MMR vaccine due to their weakened immune systems. They may be highly susceptible to many infectious diseases. 
  • Children under 12 months old do not receive the MMR vaccine, as it is less effective in younger age groups.  MMR is recommended between 12-15 months of age. More than 1% of Americans are simply too young to be vaccinated.
  • The MMR vaccine is between 90% and 99% effective in inducing measles immunity. According to CDC, an estimated 7% of children who receive just one MMR dose will remain susceptible to measles.  A second dose is recommended at age five. CDC reports that 3% of children who receive 2 MMR doses will still fail to be protected.  This leaves about 3% of fully vaccinated children over age five, and many vaccinated adults unprotected. (Additional MMR doses may be given at college entrance and to non-immune adults.)
How many children are unvaccinated? The number of children who, last year, failed to get two measles vaccinations by age 5 is 5.3% according to CDC. Some of them got one MMR dose. Let's estimate that parents of 5% of children, about 4 million, refused the MMR. This is likely an overestimate, when you consider that only 1.7% of students received non-medical waivers. 

Say there are up to 4 million vaccine pediatric refusers. If none of these children was exposed to anthrax or got an MMR later, there might be an additional 8 million adults who are unvaccinated. However, this total of 12 million Americans would be dwarfed by the estimated 23-47 million non-immune Americans who lack immunity for other reasons:

  1. those who failed to gain immunity after vaccination, or their immunity has disappeared over time (estimated 5-15% or 16-48 million Americans); 
  2. those who, because of treatment for cancer, organ transplant, autoimmune disease or the presence of HIV are at risk of dangerous infection from the live vaccine strains in MMR (estimated 2 million Americans, but possibly many more)*;
  3. those 5 million Americans who are too young to be vaccinated.
And sure enough, if you look at the 110 California measles cases associated with Disneyworld, you see this expected pattern:  12 children (11%) were too young to be vaccinated, 28 children and adults (25%) chose not to be vaccinated. 61 affected persons thought they had been vaccinated but this could not be documented for all. 8 possibly had contraindications to vaccination.
 
Let's look at measles deaths

Since 1993, I have only been able to find 3 reliable reports of deaths from measles in the United States.  (Other data suggest there might be up to 5 more cases, but I cannot find verification of them.) Deaths are extremely rare, and they are unlikely to happen to your child.  


For example, the first of the three to die was 75 years old. He was incubating measles when he entered the US from Israel.  The second was 13 years old. He developed measles after his immune system was deliberately destroyed in order to receive a bone marrow transplant. The third was a 38 year old with diabetes, congestive heart failure and COPD. All were immune compromised.

Today, there potentially might be one in 1000 deaths from measles, simply because a large portion of those who remain susceptible to measles have very serious, pre-existing medical conditions. But we simply don't know what the death rate in the US would be today, because there have been so few deaths in recent years.


Where do measles cases come from?


According to CDC, most cases of measles in the US are due to spread from imported cases. You can't stop measles without stopping travel in and out of the US.

Last year, there was a jump in cases to 644 in the US: 383 occurred as a result of Amish missionaries bringing the disease back from the Philippines. There were 23 separate measles outbreaks in 2014. Did you hear much about it? 


Despite last year's increase, over the last twenty years, on average less than one in a million Americans came down with measles yearly.


Because measles is more contagious than other common infections, when cases appear, they tend to spread. Careful case-finding and quarantines control the outbreaks. That is why we have public health professionals: to limit spread of communicable disease in this manner. The method works. Each year, small outbreaks appear and are rapidly extinguished.  For example, in 2013 there was an imported outbreak of measles in orthodox Jews in Brooklyn, New York. A total of 58 people were affected, but there was no spread outside the Jewish community.

Why is there a media frenzy over measles?


Is anything different this time to warrant the media barrage?  Not that I can tell. Only 141 people have been affected currently (and just 113 related to Disneyland), according to CDC, which is less than a quarter of total US measles cases in 2014. Is Disneyland the reason the media have hyped the outbreak? Visiting Disneyland is a rare, expensive family treat--but in this case, families got tricked. It made for an interesting story. Then, with added layers of hype and fear, the story went viral.  


The Disneyland outbreak, smaller than last year's Amish outbreak, was misleadingly spun to bulldoze the right of parents to delay or skip their childrens' vaccinations. Here's just one example, published in Forbes, and written by a scientist. Even though last year's Amish outbreak was worse, and the likely source of the epidemic was a visitor to the US, the piece blames a purported anti-vaccine movement for this outbreak: Anti-Vaccine Movement Causes Worst Measles Epidemic In 20 Years.


Soon came calls for legislation, to prevent parents from avoiding their civic duty to vaccinate.  For example:

This year’s measles outbreak has resulted in a flurry of legislative activity aimed at eliminating or making it more difficult to obtain non-medical exemptions. Such bills have been introduced in at least a half-dozen states, including California, Oregon, Maine, Minnesota, Vermont and Washington.
Yet forced vaccination still won't solve the problem of non-immune Americans. Why haven't the pundits informed themselves about this?  Why have parents been scared to death over an outbreak that is unlikely to cause permanent harm to even a single child?

Current treatments and public health programs for measles are excellent


Remember, no one has died from the current outbreak. We have excellent medical care for measles, including post-exposure vaccination for some. And if you are immune compromised, or develop a serious case, measles immune globulin is readily available, which provides the same antibodies you would develop, had you been vaccinated or previously had the disease. 


Healthcare facilities have historically been sites of measles spread. But no media are blaming them for increasing this outbreak. One advantage of the recent Ebola scare is that US healthcare facilities have gotten better at preventing the spread of viruses, including measles, within their walls. 

There has been no reduction in the rates of vaccination in the US for the past ten years.  The US Department of Health and Human Services' goal for herd immunity in its Healthy People 2020 plan is that 90% of American children receive the first MMR vaccine on time. This goal is exceeded (92%) by current vaccination rates at 19-35 months of age.  And for children entering school, 94.7% have received two doses of the MMR vaccine. We can never get this number to 100% for the reasons I listed above.

Public health policy for measles is sound.  We will always have some measles cases, but we know exactly what to do with them. The smartest thing for parents to do now is to ignore this tempest in a teapot. 


* Regarding contraindications to MMR, according to CDC reasons to avoid the MMR vaccine include pregnancy, history of allergy and many others (see here). Below are broad classes of people with immune system disorders who CDC advises should also avoid the MMR:
Immunosuppression. MMR and MMRV vaccine should not be administered to 1) persons with primary or acquired immunodeficiency, including persons with immunosuppression associated with cellular immunodeficiencies, hypogammaglobulinemia, dysgammaglobulinemia and AIDS or severe immunosuppression associated with HIV infection; 2) persons with blood dyscrasias, leukemia, lymphomas of any type, or other malignant neoplasms affecting the bone marrow or lymphatic system; 3) persons who have a family history of congenital or hereditary immunodeficiency in first-degree relatives (e.g., parents and siblings), unless the immune competence of the potential vaccine recipient has been substantiated clinically or verified by a laboratory; or 4) persons receiving systemic immunosuppressive therapy, including corticosteroids ≥2 mg/kg of body weight or ≥20 mg/day of prednisone or equivalent for persons who weigh >10 kg, when administered for ≥2 weeks (258). Persons with HIV infection who do not have severe immunosuppression should receive MMR vaccine, but not MMRV vaccine (see subsection titled Persons with HIV Infection). Measles inclusion body encephalitis has been reported after administration of MMR vaccine to immunosuppressed persons, as well as after natural measles infection with wild type virus (see section titled Safety of MMR and MMRV Vaccines) (259261).