Hepatitis A outbreak in California: Yet another reminder about the need for effective vaccination

By Marcus Oi

A s of 19 October 2017, the Hepatitis A outbreak in California has claimed 19 lives and hospitalised almost 400 individuals since November 2016. The spread of the virus is highly prevalent among the homeless community, most probably due to its method of transmission, which is via the fecal-oral route. The virus spreads like wildfire (no pun intended) in conditions of poor hygiene and sanitation, as they transmit with any fecal contact. The California Department of Public Health (CDPH) are scrambling to administer vaccines to the public as the case count rises. Vaccination is normally used as a preventive measure for individuals and the population. In this case, it is used as a form of mitigation, due to the fact that vaccination is not mandatory in the United States.

“Vaccinating people at risk of exposure is the most effective tool we have to prevent the spread of Hepatitis A infection during an outbreak,” said CDPH director Dr. Karen Smith, in a written statement.

She is not wrong. Vaccination is indeed the most effective tool. Then again, there is a need to use them to the best of their effectiveness. As mentioned earlier, vaccines are preventive tools. They are non-infectious substances, usually in the form of viral antigens, that help to trigger our bodies’ immune response BEFORE contact with the real thing. As such, they work best when administered early, certainly not when Hepatitis A is already making the news.

Remember Measles in 2014–2015?

Both the Measles and Hepatitis A outbreaks were due to the lack of herd immunity. Herd immunity occurs when a significant proportion of the population is vaccinated, thus preventing the infectious agent from spreading from one person to another. The fact that these outbreaks occur so easily in the US is a clear indication that a large percentage of the population remain unvaccinated. This implies that little has changed fundamentally in the US’s defence against infectious diseases.

It is just a matter of time before the California outbreak of Hepatitis A is dealt with. However, this outbreak will certainly not be the last. Until the US can deal with the main issue: a misinformed public, these outbreaks are going to keep coming.