Medical Director Notes

Staying Resilient: Controlling Hepatitis A Outbreak

City personnel evacuated Kensington’s last homeless encampment during January’s polar vortex. Forty-five people left the Emerald City encampment and were referred for a combination of housing, medical or social services as a part of Mayor Kenney’s Philadelphia Resilience Project.

Launched in October 2018, the Philadelphia Resilience Project aims to bolster affected Philadelphia neighborhoods by uniting partners to address homelessness, drug addiction, violence, metal health challenges, and neighborhood clean-up. While these are all crucial needs, it is also important to remember that persons and communities affected by the opioid crisis are at higher risk for certain infectious diseases. Indeed, Philadelphia has seen increases in Hepatitis A, B and C, HIV and syphilis within neighborhoods most affected by the crisis. Hepatitis A has been particularly concerning.

Now is the time to immunize everyone who should get a Hepatitis A vaccine and the Immunization Program is here to support your efforts

Many states are experiencing outbreaks of Hepatitis A, especially among homeless persons. Hepatitis A spreads when stool from infected persons contaminates food, water or other surfaces. It is much easier for the virus to spread when it is difficult to wash hands or have regular access to a bathroom. Hepatitis A can also be spread through sexual activity or sharing needles. That is one of the reasons why there have been a rising number of outbreaks in communities affected by homelessness and injection drug use. Since March 2017, several states have declared Hepatitis A outbreaks for a total of more than 4,000 cases, the majority of whom have been hospitalized and over fifty have died. Pennsylvania joined the list of affected states in November 2018. Fortunately, there are things we can do to prevent the outbreak from escalating here…vaccinate!

Hepatitis A vaccines were first introduced in the U.S. in 1996. Since then they have been routinely recommended for all infants 12-23 months old and for anyone at increased risk for Hepatitis A exposure. Why vaccinate 12 month olds? When Hepatitis A was more common, it was often spread by young children who would be more likely to have asymptomatic infection and could spread virus without knowing it. This strategy helps reduce the amount of hepatitis A in the community – but it won’t stop all transmission. Only about 70% of infants get the vaccines. And there are many adolescent and adults who didn’t have a chance to get vaccinated as kids. Now is the time to immunize everyone who should get a Hepatitis A vaccine and the Immunization Program is here to support your efforts

• If you see children and adolescents in your practice, check whether your patients have received Hepatitis A vaccine and catch them up if they haven’t. If you see adults, offer Hepatitis A vaccine to everyone but make sure you give it to your patients with a history of drug use or homelessness. Use our immunization registry, Philavax, to check your patients’ immunization histories.
• The Vaccines for Children (VFC) and Vaccines for Adults at Risk (VFAAR) programs can help you provide vaccines for publicly, under- or uninsured kids and uninsured adults.
• If any of your patients have signs of acute hepatitis (fever, jaundice, nausea, light colored stools), test for Hepatitis A and report any positive results. We can help make sure that the virus won’t spread to others.
• Check the Health Information Portal for more information about Hepatitis A and other infections affecting persons who are homeless or use drugs.

In October and November, our team provided 222 Hepatitis A and over 200 influenza vaccines to people living in and around encampments in Kensington through street outreach. We have also collaborated with Prevention Point, Philadelphia’s needle exchange program, to provide vaccines to their clients. While we have been able to target a high risk community, let’s do what we can to increase Hepatitis A vaccination rates across the city.

Through partnership, we can contribute to resilient communities.

Notes from the Medical Director

HPV vaccine for adults?

On October 5, 2018, the Food and Drug Administration expanded the age range for HPV vaccines to include 27-45 years old men and women. The change has gotten a lot of coverage in the media and perhaps you have been getting questions about the expanded age range from patients, family or friends. Why was this change made and what does this change mean for you?

FDA approval does not mean that recommendations have changed.
While the FDA has approved the expanded age range, the Advisory Commission on Immunization Practices (ACIP), who makes our recommendations about when and to whom to give approved vaccines, has not yet changed their recommendations about who should get HPV vaccines. So, for now, HPV vaccines recommendations still focus on 9-26 year old males and females.

The committee has been reviewing information about not only how well HPV vaccines work, but also how much of an impact it is likely to have on preventing HPV infections, in this older age group. Adding a new recommendation takes resources to make sure there is enough vaccine supply, raise awareness and get providers ready to stock and recommend a vaccine. The ACIP considers all of this before making changes to the program.

Why wouldn’t HPV vaccines be recommended for adults, especially since HPV is a sexually-transmitted infection?
Current recommendations for HPV vaccines target 11-12 years old adolescents for routine vaccination with catch up through age 26. Our current recommendation target younger age groups for several reasons:

1. The goal of vaccination is to get everyone protected BEFORE exposure: HPV vaccines work by providing immunity before exposure to the HPV types covered by the vaccine. Since HPV is a sexually transmitted infection, that means before onset of sexual activity. The best way to make sure this happens is to get kids vaccinated just as they are entering adolescence, well before likely exposure. HPV is very common- almost all of us are exposed at some point during adolescence and adulthood.
2. HPV vaccine can be given as a part of the adolescent vaccine platform: This approach also works well because young adolescents are coming in to get other vaccines, Tdap and MCV4, when they are 11 or 12 years old. This an excellent time to make sure adolescents have everything they need to keep them healthy as they enter middle and high school.
3. We have data that shows how well the vaccines work in this age group: The immune response in younger adolescents is so good, only 2 doses of the HPV vaccine are needed if you start the series before age 15 years, compared to 3 doses for older teens.

Recommendations have not included adults because as we get older, we are more likely to be exposed to HPV. Since the vaccine protects us BEFORE exposure- it won’t help if we have already been infected by the types covered by the vaccine. So, for now, recommendations focus on early protection to get as much impact as possible.

If adults are more likely to already be exposed to HPV, why did the FDA approve the expanded age range?
Even though adults are more likely to be already exposed to HPV, adults are not likely to have been exposed to ALL the HPV types covered by the vaccine. That means that there may still be some benefit to vaccination. Let’s say you have a patient who has been exposed to types 6 and 16. Your patient would still be protected against the 7 other types covered by the vaccine.
To make its decision, the FDA considered benefit by reviewing studies that show how well the vaccine works in women and men ages 27-45 years old. These studies looked at two things: the immune response (antibody levels) and vaccine effectiveness (ability to prevent HPV disease) in this age group. These studies showed that there is a good immune response but effectiveness is not quite as high since adults may have already been exposed to HPV before vaccination. No studies showed any safety issues.

Does this mean that I should or shouldn’t vaccinate adults >27 years old?
Remember that recommendations from the ACIP still have not changed. Keep emphasizing routine vaccination for 11-12 year olds. This is the best and most cost-effective way to ensure good protection before exposure to any HPV and reduce the overall prevalence of HPV in the community. For this reason, it is difficult to know whether HPV vaccines will be recommended universally for adults aged 27-45 years old. But, there still may be room for individual decision making. While adolescents and young adults are at highest risk of first exposure to HPV once they become sexually active, that does not mean the exposure risk goes away. HPV vaccination for 27-45 year old adults could still provide protection against some HPV types, especially for adults who remain at risk of exposure (i.e. have a new partner). While our HPV vaccination rates have been improving, we are still below Healthy People 2020 goals so there are unvaccinated adults out there.

More to come…

Notes from the Medical Director

How bad can the flu get?

Flu season is challenging. First, we need a new flu vaccine every year because the flu virus is always changing.  Before each flu season, a new flu vaccine is developed to match the flu strain that scientists expect will be dominant during the upcoming season. Then, vaccine producers start manufacturing the vaccine and distribute it all over the world. Finally, local public health professionals like us here in Philadelphia work hard to remind everybody to get a flu vaccine as early as September to make sure everyone is protected before flu arrives.

From vaccine development to vaccine delivery, it is a large amount of work. But it is important work because flu is serious, every year. During the height of a bad flu season, up to 8% of all emergency room visits in the USA – 1 out of every 12 – is somebody who’s sick with the flu and hundreds of thousands of people are hospitalized with illness caused by the flu. Last year’s flu season killed an estimated 80,000 people in the USA.

Despite flu’s severity every year, too few people get the flu vaccine – immunization rates hover around 40% in the USA. Why? Often, I think we underestimate how bad flu can be. We call lots of things ‘the flu,’ including milder infections like the common cold. That can lead us to think that the flu does not really make you very sick. But influenza can invade your lungs and make you feel horrible. In severe cases, your lungs can get so inflamed that they stop working.

The worst example of how bad the flu can get was the 1918 flu pandemic. It was so bad that “cities ran out of wood for coffins” as the virus killed 3 to 5 percent of the world’s population – an estimated 50 to 100 million people. The 1918 pandemic was caused by a new strain of influenza. We have had pandemics since that time and will probably have more the future. And we will continue to have flu epidemics every season. While we now have more tools to prevent and treat influenza, we need to keep being prepared and keep working to reduce the toll that the seasonal flu takes on our population.

To help, we’ve got a Flu Toolkit that health care providers can use to boost flu vaccination rates at their clinics this fall and winter – and, of course, resources for Philadelphia residents to Get Your Annual Flu Shot.

Notes from the Medical Director

The historical impact of vaccines

It can be so easy to lose sight of the incredible impact that vaccines have had on our society. Mike Bostock, a data visualization specialist, reminds us of the history of the measles vaccine with the data visualization below.

Measles used to be incredibly common, but when the vaccine was introduced to the US in 1963, cases plummeted. Bostock’s visualization shows this clearly: moving from left to right, the darker colors begin to fade, just as the number of cases in each state decline immediately following the introduction of the vaccine.

If there are so few measles cases in the U.S., do we still need to maintain high immunization rates? Yes. The dramatic impact of measles vaccine introduction is testament to both the individual and community effects with immunizations.  Vaccinated children were no longer getting infected themselves, and they could no longer spread measles to others.  But to see the community effects of measles vaccines, we do need high vaccination rates.  Measles is one of the most contagious vaccine-preventable disease out there so almost everyone needs to be protected to stop transmission.  When we keep our measles vaccination rates above at least 92%, we eliminate measles outbreaks.

Measles still affects about 20 million people per year worldwide.  No other vaccine-preventable illness causes as many deaths.  Most cases occur in developing areas of Africa and Asia but there are also tens of thousands of cases in several European countries due to decreasing immunization rates. In fact, the Centers for Disease Control and Prevention has issued travel advisories for places from which many of us may receive visitors or visit ourselves.  So the likelihood of being exposed to measles is very real.  If communities do not maintain high immunization rates, outbreaks can happen here as well.

Here at the Philadelphia Department of Public Health, we’ve done similar work to highlight the history of vaccines and their important public health impact. The history of vaccine-preventable diseases in Philadelphia shows how these diseases used to kill nearly 3,000 Philadelphians per year. As more vaccines were licensed and distributed, this death toll fell steadily until the modern era, when vaccine-preventable diseases only kill 11 Philadelphians per year.  Let’s work together to make sure these trends don’t change.

Measles in the USA

Notes from the Medical Director

Is it time for a Lyme vaccine?

The New York Times recently reported what we’ve seen for several years now: that Lyme disease and other tick-borne diseases are spreading.

The US Centers for Disease Control and Prevention (CDC) and the Environmental Protection Agency (EPA) have both observed that Lyme disease has been rising. In fact, since 1990, Lyme disease cases in the USA have tripled.

So what’s going on? Well, climate change is probably a factor. Lyme disease is spread by blacklegged ticks, which are commonly found on deer and white-footed mice. Because of changes in weather patterns, their habitat is expanding – and, milder winters mean that fewer ticks die off each winter.

Health officials are pretty sure that this is only going to get worse. Whether you spend time in city parks or live in wooded areas, it is possible to find blacklegged ticks – and there are things we can do to prevent getting bitten by ticks.

What about a Lyme vaccine?

In 1998, a vaccine for Lyme disease was released. Four years later, the company that made it took it off the market: it just didn’t sell very well. There were concerns that the vaccine could be linked to autoimmune diseases, even though all of the studies about the vaccine found that it was safe. Plus, a lot of health care providers were unclear about who should get the vaccine.

That was several years ago. Now, with Lyme disease on the rise – and expected to continue rising – there are initiatives to develop a new vaccine to prevent Lyme disease and to also potentially prevent other infections spread by ticks. If a vaccine comes to market, then the US Advisory Committee on Immunization Practices (ACIP) would review the evidence and make recommendations about who should get the vaccine, and when.

Lyme disease can be serious – people with the disease can have symptoms that range from a rash to joint swelling to neurologic symptoms. No matter how it presents, Lyme disease is treatable and responds well to antibiotics, but it can sometimes take time for symptoms to go away completely. And while the CDC counts about 30,000 people per year in the USA getting Lyme disease, they’re pretty sure that the actual figure is much higher – up to ten times higher – due to cases not getting properly diagnosed or reported.

This is the time to build up our prevention tool box for Lyme disease. Preventing its spread will take a lot of different strategies: teaching the public to prevent tick bites, developing better insect repellents, and reducing tick habitat around people’s homes. But adding a vaccine to our prevention options could be another powerful tool.

Notes from the Medical Director

The return of the flu spray: what changed?

For the 2018-19 flu season, the Advisory Committee on Immunization Practices (ACIP) added the intranasal live-attenuated influenza vaccine (LAIV) back to the list of recommended flu vaccines for children and adults. The LAIV is a flu vaccine given as a nasal spray instead of as a shot – which a lot of patients liked.

LAIV, the flu spray, was fist introduced in 2003. It initially appeared to work really well in children, so in 2014, the ACIP made a recommendation to prefer it. But 2 years later, they changed their minds, recommending against it for the past few seasons because of LAIV’s poor effectiveness.

So what changed? Why is it being reintroduced now? Let’s take a deeper dive.

How is LAIV different from other flu vaccines?

Most flu vaccines are “inactived influenza vaccines,” or IIVs. These are made by growing the flu virus in eggs, purifying it, and then inactivating the virus – killing it. It’s then given as a shot that teaches our immune system how to respond to an actual live flu virus – even though the IIV can’t reproduce to cause a flu infection.

We’ve been using this method to make flu vaccines since the 1940s. Since the flu virus changes each year, we have to make a new vaccine each year so that the vaccine matches up with the flu strain that’s likely to emerge most strongly each year.

• IIV: inactivated virus, given with a shot
• LAIV: weakened virus, given with a nasal spray

Unlike the IIV, the LAIV (live attenuated influenza vaccine) is made by growing the flu virus in egg cells, and then just weakening it instead of inactivating the virus. It’s then given as a nasal spray instead of a shot – and the weakened virus can reproduce just enough to spark an immune response in a patient’s body. Though the virus is live, it’s too weak to cause infection; and since it’s administered in the nose – which is how a lot of people are exposed to the flu – it can be an especially effective way to provide protection: following the same path the disease would follow.

So why was the LAIV removed from the list of recommended vaccines in 2016?

When LAIV was first introduced, it did appear to work a little better, especially in children. So in 2014, the ACIP gave LAIV a preferential recommendation – preferring the spray over the shot.

Shortly after that – once the spray was used more widely – the ACIP’s research showed that the spray stopped working as well as it initially did. For 3 years in a row, the spray didn’t perform any better than the shot. In fact, it was less effective. So, while the CDC worked to understand what happened, the ACIP removed their recommendation for the spray (LAIV).

So what happened?

Every flu vaccine protects against 3 to 4 strains of the flu. And, the CDC found that one of the flu strains in the spray didn’t reproduce well enough to spark a good immune response in patients. Since the spray relies on weakened but live virus to reproduce in order to trigger protection in a patient, this was a problem.

This flu strain was H1N1. We had several seasons where a lot of the flu disease was due to H1N1 – so the spray just didn’t provide as much protection as originally hoped.

Okay – so now the spray is back?

Yes. Once the CDC figured out the problem with the spray, the vaccine manufacturer replaced the H1N1 strain – which wasn’t reproducing well – with another strain that works better. They also checked to make sure that there’s a good immune response to the new LAIV.

The ACIP reviewed all of the changes and felt that the problem was addressed – so the spray was added back to the list of recommended flu vaccines for anyone between age 2 and 49.

Even though the ACIP recommends the spray, the American Academy of Pediatrics recommends the shot. Why do they disagree?

When the ACIP reviewed information about the new version of the spray – including studies on the spray’s effectiveness from other countries that continued to use it – they felt that the strong immune response was a good sign that the spray should work at least as well as the shot.

The AAP was also reassured, but they wanted to see more information on protection against the actual disease before they strongly recommended it. So, they decided to recommend the inactivated vaccine (the shot) over LAIV (the spray) until we learn more about the spray’s effectiveness once it’s used more broadly.

So what should I do?

Offer both vaccines.

The effectiveness of the flu vaccine always varies from year to year as researchers try to match the vaccine to the flu virus that they expect to dominate the flu season. Despite varying effectiveness, vaccination is our best method of protection against this virus that kills tens of thousands of people in the USA each year. Since some people decline the flu vaccine because of a fear of injections, having the spray available may increase the likelihood that patients will accept the vaccine.

Patients look to us – health care providers – to listen to their concerns and make recommendations that will keep them healthy. So let’s offer them choices that can help protect them, and let’s remind them that we get our flu vaccines to protect ourselves, our children, our patients, and our community too.