Top 8 Vaccination Myths

VaccineMyth #1 MMR Vaccine causes autism.

This myth started with an article published in 1998. It was a case series of 12 children associating the MMR vaccine with development of autism. This article has since been redacted as it was found that the authors basically falsified facts. Since then, there has been more than 10 studies about MMR and autism all reporting no association. The latest of these was released 4/16/2019 in the Annals of Internal Medicine journal. It followed 657,461 children born in Denmark between 1999-2010. It concluded that there is no increased risk for autism after MMR vaccination.

Myth #2 Kids receive too much vaccination at one time if the recommended immunization schedule is followed.

Babies and toddlers sometimes get 5 shots in a well child visit. However, they are also  exposed to countless bacteria and viruses everyday. They touch dirt and then put their hands in their mouth. Immunizations are negligible in comparison. In immunizing kids, you are teaching their immune system to protect them by introducing a controlled and measured dose of the weakened or dead virus or bacteria. A kid getting multiple shots at one time will not “overwhelm” their immune system. Our immune system is continuously getting replenished, up to 2 billion cells each day.

Myth #3 “Natural” immunity is better.

Actually getting sick with measles (or other vaccine-preventable diseases) MAY result in a longer-lasting immunity. However, actually getting sick with these diseases also comes with risk of complications. One in 4 who gets measles end up in the hospital. One in 1,000 can end up with encephalitis. One in 1,000 can die even with best care. Compare that with vaccination risk of severe allergic reaction which happens in 1 in a million.

Myth #4 Vaccines have unsafe toxins.

Formaldehyde, mercury, and aluminum can be found in TRACE amounts in some vaccines (of note, not in MMR). These are in the amounts that would not cause any harm. One gets more than 100 times the amount of aluminum from a dose of an antacid.

Myth #5 Vaccination can cause one to get the disease and to “shed.”

In the 1950s, the oral polio vaccine caused recipients to “shed” the virus from their stool. Contact with the feces and subsequent ingestion caused infection. However, this vaccine is no longer used in the US. Shedding is impossible with killed vaccines or those that only contain isolated proteins from the virus as these cannot replicate and be “shed.” MMR is a live virus vaccine. However, it does not cause “shedding.’ An MMR-vaccinated individual is not expelling vaccine-strain measles virus in the air, which is how “natural” measles is spread. They also do not shed the measles virus in their stool as that is not how measles affect the body.

Myth #6 Sanitation, and not vaccination, is responsible for the significant decrease in the infection.

Sanitation and access to safe water had a great impact in decreasing cholera and other oro-fecally transmitted diseases. However, no matter how clean your surroundings are, if a person with measles coughed out virus in the air in the same room as you and you are not immune, there is a 90% chance that you are going to develop measles. The impact of vaccination can be seen with how much the incidence of the disease dropped after its introduction.

Myth #7 Vaccines contain fetal tissues and by using them one is supporting abortion.

In the 1960’s, from elective termination of two pregnancies, two cell strains were developed, WI-38 and MRC-5. Neither abortion was done for the purpose of vaccine development. Certain viruses infect only humans. Because of this, they grow best in human cells. Cells can only divide and reproduce a certain number of times before dying. But, fetal cells are capable of doing this for many more times before dying. The same cell strains developed in the 1960s have continued to grow in the laboratory and are used to make the vaccines against varicella, rubella, and hepatitis A today. 

Myth #8 Muslims and Jews cannot receive vaccines as they contain pork.

Some vaccines such as MMR and varicella, contain porcine gelatin to stabilize them. In 1995, Islamic scholars met and determined that the transformation of pork products into gelatin alters them sufficiently to make it permissible for observant Muslims to receive vaccines containing pork gelatin. ( With regards to Jewish laws, a rabbi stated that non-oral porcine products are not a problem (



Understanding TB Transmission with Whole Genome Sequencing

K. Bjorn-Mortensen, B. Soborg, A. Koch, K. Ladefoged, M. Merker et al. Tracing Mycobacterium tuberculosis transmission by whole genome sequencing in a high incidence setting: a retrospective population-based study in East Greenland. Scientific Reports 6, Article number: 33180 (2016) doi:10.1038/srep33180

Genotyping of TB, which has been available since 2004, first gave us a peek into better understanding of TB transmission as well as relapse vs reinfection. If the TB bacteria obtained from two patients have the same genotype, one may have reason to believe that the bacteria that caused disease in each are related (they may have gotten it from each other or a common person, or something to that effect). Similarly, if a patient had TB, got cured then had TB again, if the bacteria from the two instances match in genotype, one may be led to believe that it was the same disease that relapsed. Whereas, if the bacteria from the two instances do not match, the second episode may be due to reinfection rather than relapse. Genotyping targets genetic material that are mostly stable over time. However, it only represents <1% of the TB genome.

2012 brought forth whole genome sequencing (WGS) of TB. Now we are talking about approximately 90% or more of the TB genome. With this, even just one nucleotide change can be noted. This is called a single nucleotide polymorphism (SNP). TB genome changes very slowly such that it accumulates only 0.5SNP/year. Therefore, when the TB bacteria obtained from different patients have only few SNPs differences, that means these bacteria are closely related and signal recent transmission. Here in Austin, we have several cases that share identical WGS, meaning no SNP were identified. With common epidemiological links as well, this is highly suggestive of recent relationship between these cases. Science has afforded us this knowledge. Hopefully we can act on it.

Image above is from: K. Bjorn-Mortensen, B. Soborg, A. Koch, K. Ladefoged, M. Merker et al. Tracing Mycobacterium tuberculosis transmission by whole genome sequencing in a high incidence setting: a retrospective population-based study in East Greenland. Scientific Reports 6, Article number: 33180 (2016) doi:10.1038/srep33180.

LGV mimicking IBD in Austin


Original Title: Lam_184cc.jpg
Depicted in this 2007 photograph, CDC microbiologist Dr Cheng-Yen Chen, was shown preparing a pyrosequencing experiment in order to differentiate between Chlamydia trachomatis L-serovars responsible for lymphogranuloma venereum (LGV), and other chlamydial serovars. Organisms of the same genus are further subdivided into serovars, or serotypes, which group these organisms based upon their constituent intracellular antigenic profiles.Dr. Chen is a National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP) staff member, who works inside the center’s Laboratory Reference and Research Branch (LRRB). Image credit: CDC/ Hsi Liu, Ph.D., MBA, James Gathany



Lymphogranuloma venereum (LGV) is a sexually transmitted disease caused by a variant of Chlamydia trachomatis different from the variant causing urethritis in men and cervicitis in women. In contrast, it causes genital ulcer in the first stage, while the second stage can be swollen, tender, and enlarged lymph nodes or proctocolitis with rectal discharge. It is endemic in tropical areas of the world. However, it has been increasingly reported in developed countries since 2003. There has been outbreaks reported in Western Europe and North America, primarily in men who have sex with men (MSM) who are also HIV-infected, mostly presenting as proctitis. 

LGV is not a reportable disease in Texas. However, the last known case of it in this state was in 2013. Beginning last year, several MSM with HIV have been diagnosed with it here in Austin. Providers here in Austin should be aware of this. LGV can present as proctitis and can get mistaken for Inflammatory Bowel Disease and not get appropriately treated causing complications for the patient such as fistulae, strictures, and infertility; as well as spread of the infection itself as well as of HIV.

False: Flu vaccine is only 10% effective this season

First of all, where did this information come from? This came from the vaccine effectiveness estimate from Australia ( ). More specifically, the 10% effectiveness was only for one strain, the A(H3). The estimates for the other strains were higher at 50% for strain A(H1) and 57% for strain B. The overall vaccine effectiveness was reported to be 33%. These data are out already as the flu season in Australia is during their cold season in May to September.

Given where this data came from, can this be applied to the US? On one hand, yes, because the composition of the flu vaccine in Australia is similar to that of the flu vaccine in the US.  Each flu season, the WHO gives recommendation on the composition of the flu vaccine for the northern hemisphere and another for the southern hemisphere ( However, in Australia, flu vaccination is recommended only for the elderly, pregnant and chronically ill ( Contrast this to the CDC recommendation for the US, which is everyone 6 months and older, excluding only those with medical contraindications. This difference is important to consider because the elderly and the chronically ill are known to not respond as well to vaccines compared to other members of the population. Therefore, despite receiving vaccination, this group has increased risk of not developing immunity, as if they did not receive any vaccine at all.

Historically, vaccine effectiveness in the US has ranged from 10%-60% beginning 2004-2005 season to 2016-2017 season ( Do we have the number yet for this season? No, because the flu season has not ended yet and therefore all the numbers that are given out are just estimate and are subject to change. Even if turns out to be 10% at the end of the season, does that mean we shouldn’t have used the vaccine? No, because if people are going to get sick, you want all the protection you can get from complications and death (one example: We know flu kills. Car accident kills. Would you want to be in an accident without a seat belt?

How flu kills

CDC/ F. A. Murphy

Having already claimed the lives of 53 children in the US this season, flu is definitely showing its deadly side. However, it still more commonly presents like a mild illness that goes away on its own after a week or so. Thus, some wonder how people die from the flu.

What usually kill people with the flu are the complications that happen from it.

Sometimes, the whole body responds to the infection with overwhelming and dysregulated inflammation which can then lead to multiple organ failure and death. This is sepsis. In other times, the virus directly affects the lungs causing pneumonia. Bacteria can take advantage of the damage being caused by the virus and cause pneumonia as well. Also, inflammatory response can also involve the heart, causing what is called myocarditis; the brain, causing what is called encephalitis; the covering of the brain, causing what is called meningitis; the spinal cord, causing what is called myelitis; and the covering of the nerve cells, causing a paralyzing illness called Guillain-Barré syndrome.

Flu may not always kill, but it can in so many ways. So, take your flu shot. It may not completely prevent you from getting the flu. It can, however, protect you from dying from the flu.

Avoiding the Dreaded Flu

There are so many advices going around these days on how to avoid the dreaded flu. Take this supplement, take the flu shot, cover your mouth when you cough, use this air filter, etc. Yes, advise those who are sick to stay home and practice cough etiquette. But what can you REALLY do, as the (still) healthy person, to avoid the flu.

Flu viruses are transmitted from person to person through droplets of respiratory secretions when people with flu cough, sneeze, or talk. These droplets can travel in the air up to about 6 feet away. They are also spread when people touch something contaminated with it and then touch their mouth, eyes, or nose. Knowing this, what can you do to avoid it?

First, wash your hands often with soap and water. They’re going to get dry if you do this properly. Therefore, use lotion as well.  Avoid touching your eyes, nose, and mouth. Clean objects, especially those frequently touched by many people, and follow with an EPA-registered disinfectant. Try to keep your distance from sick people. I know. That’s easier said than done. It still needs to be said.

Should you take those supplements to “build your immune system”? No supplement has been proven to “build the immune system” and prevent one from getting sick. Aside from supplements not being regulated (therefore, you may not really know what is really in them), they may cause unintended effects. Take for instance Vitamin C. You can get kidney stones from too much of it. Vitamin A in pregnancy is teratogenic at high doses. You can turn yellow from too much beta-carotene. Heck, even drinking lots of water has side effects. If you have heart failure or cirrhosis, please follow your doctor’s advice as usually you may be on fluid restriction. I have had patients with these conditions develop fluid in their lungs and developed difficulty breathing after being advised to drink lots of water by well-meaning friends, when I was still working in a hospital. Drinking lots of water will not prevent you from getting the flu.

What about air filters? There is nothing really available commercially (that is, available to regular consumers outside of the health care settings) that filters out influenza aerosols. It is not cost-effective since influenza is transmitted over relatively short distances as mentioned earlier.

Lastly, get your flu shot. It’s the best way to protect yourself. And, if you still end up getting the flu despite getting the shot, then at least your risk of dying from the flu is much less.

Tuberculosis: claiming lives since 4000BC

Yes, TB is old. That does not mean it is not relevant anymore. A common misconception is that it is rare nowadays. Nothing can be further from the truth. Beginning 2014 continuing to 2015 (2016 data not yet available), TB has surpassed HIV as the number one infectious disease killer in the world. That is just sad given that TB is both preventable and curable. Having someone in this modern age die of a disease that claimed the lives of Nefertiti and her pharaoh husband Akhenaten is somewhat embarrassing for the human race. Let’s think TB to stop TB.

Think TB. Stop TB.

Too many times I have seen doctors miss the diagnosis of tuberculosis (TB) despite seeing an apical cavitary lesion on the patient’s radiograph. Delayed diagnosis in this case is not only unfortunate for the patient. It is also a public health issue as more people are unnecessarily exposed to a contagious disease that could have been prevented by earlier proper diagnosis. Health departments can only do so much if private clinicians fail to consider TB in their differentials.  Having not been diagnosed properly, their patients with the airborne disease continue to spread it. It is true that unlike in many other countries, TB is not endemic in the US. However, that doesn’t mean we can forget about it. Doing so is one reason why TB continues to sneak up on us. Every doctor, even those in the private sector, has a public health responsibility to have TB in their differentials as appropriate.

Preventing HIV

There may not be a vaccine (yet) for HIV. However, one can take a medication to prevent having HIV, especially if one is at risk for acquiring it (such as persons engaging in high-risk behavior or if they have partners who are HIV-positive). This is called Preexposure Prophylaxis (in short, PrEP). This is in contrast to Postexposure prophylaxis (in short, PEP), in which the medications are taken after a person has been exposed to HIV already. The US Public Health Service actually released a clinical practice guideline on PrEP in 2014. It urges clinicians to consider offering PrEP as an HIV prevention option to their patients at substantial risk of acquiring HIV infection. However, despite these, PrEP is still not very commonly employed. One hurdle may be that many clinicians are not comfortable with prescribing anti-retroviral medications. Also, even after getting a prescription for Truvada (the medication used to prevent HIV in PrEP), the patient still has to navigate the health system in order to get it, which includes asking his/her health insurance provider to cover the medication and coordinating with other patient assistance programs and deal with the co-pays, deductibles, and prior-authorization requirements. Luckily, in Austin, we have the Austin PrEP Access Project that helps people interested in PrEP in navigating the health system. More information can be found at