Tag Archives: Vaccine

Vaccine Induce False Positives in Preventative HIV Trials

Everyday there are over 7500 cases of human immunodeficiency virus, HIV, that are reported all over the world and the need for an effective Food and Drug Administration-approved vaccine is constantly growing. Researchers have proposed various approaches that have reached clinical trials of 30,000 participants, however, preventative HIV-1 vaccines have the risk of giving false test results. This is due to the ability for trial participants to generate HIV antibody responses that are induced by the vaccination. During routine HIV testing that use antibody detection methods, false positives may be found and can cause an incorrect diagnosis.

Fig. 1: Vaccination via Needle                       Source: Flickr by VCU CNS

This study assesses the appearance of vaccine induced sensitive/reactivity, VISP, in HIV vaccine trials, which were delivered in different systems and with HIV inserts. In 2010, Dr. Baden and her team used three FDA approved enzyme immunoassay (EIA) HIV antibody kits, which detect VISP by identifying the antibodies that were induced and a diagnostic HIV algorithm that examines the frequency of VISP in healthy adults.

Out of the 2176 participants that were free of the HIV infection and given a vaccine, 41.7% of them had VISP. However, the frequency of VISP varied between vaccine types; 86.7% adenovirus 5 product, 53.4% of poxvirus and 6.3% of DNA -alone product recipients that were given those vaccines had VISP.

Fig. 2: 2176 Non-HIV vaccine recipients with true negative or false positive results

The HIV testing kits also varied in VISP results between 40.9% and 8.8% of participants. Their findings suggested that VISP depended on the vaccine that was administrated as well as the EIA used.

Fig. 3: Microscopic HIV Budding                                    Source: Wikipedia

If VISP induces false positive results, it could affect these participants’ opportunity to donate blood or organs, obtain medical or life insurance, hired for employment and even being able to immigrate into certain countries. Testing for VISP is crucial after every study to ensure no societal harm or incorrect reports enter the health system. However, some clinicians may glance over full patient history due to added time and cost.

The development for a vaccine gets closer to becoming approved but there are still many obstacles that researchers must face. With the race against the clock, people who are diagnosed with HIV slowly acquire AIDS if not treated. If researchers can find a preventative vaccine, HIV/AIDS could be avoidable in the future.

-Tiffany Liew

 

Rise of the Anti-Vaccinations: The European Outbreak of the Measles Virus

With over 20,000 cases and 35 deaths, measles is on the rise again in Europe. Could the “anti-vax” movement be to blame?

Figure 1: Vaccine being drawn into a needle Source: Flickr

According to the World Health Organization’s (WHO) most recent report, after a record low of 5273 cases in 2016, there were four times as many cases of the measles virus in 2017.

Of the 53 countries in the region, 21 had reported large outbreaks. A classification of a large measles outbreak includes over 100 reported cases. Some countries on this list include Germany, Greece and the United Kingdom. The countries that top this list are Romania, Italy and Ukraine, all nearing or over 5000 reported cases.

Figure 1: List of all European countries that have large outbreaks of the measles virus Source: WHO Europe

So how could Europe go from a record low to a four-fold increase in only a year?

The WHO claims that this is because of the decrease in routine vaccinations, interrupted supply of vaccines and underperforming disease surveillance systems.

In the retracted 1998 publication from the Lancet, a medical journal from the United Kingdom, an article stated that there was a correlation between the measles vaccination and autism.

Although this statement was highly discredited, the anti-vaccination (anti-vax) movements in recent years have surged from these false claims. The influence from the opinion of the “anti-vax” movement has led to an overall loss of trust in vaccinations.

Figure 3: Bumper sticker promoting the views of the anti-vax movement Source: Flickr

Some countries, such as Italy, have had government intervention where legislation requires children to get vaccinated if they plan on attending state-run schools.

The French Health Ministry has also promised to enforce mandatory vaccinations for young children by early 2018.

Unsurprisingly, this decrease in vaccinations is the largest risk in spreading the measles. Any individuals unvaccinated, regardless of age, are at risk of catching and spreading the virus to others who are not protected.

For now, the WHO intends to increase vaccination rates in Europe by improving the supply chain of vaccines and informing the public with awareness campaigns.

-Brandon Kato

References:

Europe observes a 4-fold increase in measles cases in 2017 compared to previous year http://www.euro.who.int/en/media-centre/sections/press-releases/2018/europe-observes-a-4-fold-increase-in-measles-cases-in-2017-compared-to-previous-year (accessed Feb 25, 2018).

Wakefield, A. J. The Lancet. 1998351(9103), 637–641.

Italy makes 12 vaccinations compulsory for children http://www.bbc.com/news/world-europe-39983799 (accessed Feb 25, 2018).

8 nouveaux vaccins obligatoires pour les enfants de moins de 2 ans http://www.gouvernement.fr/argumentaire/8-nouveaux-vaccins-obligatoires-pour-les-enfants-de-moins-de-2-ans (accessed Feb 25, 2018).