A person gets a monkeypox vaccine.Share on Pinterest
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  • The HHS renewed its public health emergency declaration for monkeypox.
  • Over 1 million people have now been vaccinated against the disease.
  • Shortages of monkeypox vaccines and high demand saw the FDA approve ‘one-fifth’ doses.
  • The number of follow-up doses has been low due to concerns about side effects, namely soreness and redness at the injection site.

The Department for Health and Human Services (HHS) has renewed its declaration that the monkeypox outbreak is still a public health emergency.

The HHS first issued the public health declaration in August.

The renewal comes after over 28,000 cases of monkeypox have been diagnosed in the U.S. and eight deaths, according to the U.S. Centers for Disease Control and Prevention.

After the first case of monkeypox was reported in the U.S. in May, case numbers quickly climbed—and calls for vaccinations soon followed.

Vaccines were introduced in the summer and, so far, over 1 million have been administered across the country. Yet their rollout hasn’t been quite so straightforward.

Limited dosage supplies meant that only certain individuals were deemed eligible for the jab which created a scramble for vaccination appointments. In light of this, the Food and Drug Administration (FDA) authorized that a single dosage could be split into five to reach more people—prompting concerns that protection levels may be compromised.

Meanwhile, some recipients are developing a red, painful mark at the injection site.

Some outlets including The Washington Post reported this prospect is deterring recipients—primarily men who have sex with men—from getting either their initial or follow-up dose, partly for fear of stigmatization.

Let’s take a closer look at some issues that have been arising and what implications they have for those receiving the vaccination.

Before delving into concerns around smaller dosage amounts, it’s important to understand how most vaccines are delivered regardless of what disease they provide protection against. There are three types of injectable vaccines: intradermal, subcutaneous, and intramuscular.

“Most vaccinations currently available, like SARS-CoV-2 or influenza vaccines, are intramuscular injections,” Dr Michael Chang, a specialist in infectious diseases at UTHealth Houston and Memorial Hermann Hospital, explained to Healthline.

Common intramuscular injection sites include the upper arm or leg. Furthermore, he noted, “for most authorized or fully approved vaccines, injecting deeper into the muscle maximizes the immune response against the vaccine, optimizing protection. [It also] minimizes the frequency of local injection site reactions.”

In subcutaneous injections, the needle is “inserted into a layer deeper than the skin, usually the fatty layer between the skin and the muscle,” said Chang. The JYNNEOS monkeypox vaccine was initially approved for administration in this way.

However, the approach “isn’t used as much for vaccines, as the immune response in the skin may not be as vigorous, and you have more local site injection reactions,” Chang revealed.

This leads us to intradermal injection, whereby the vaccination is delivered to the top layer of the skin. This is now the method being used for monkeypox vaccines. So why the switch?

“Often, intradermal vaccines require a lower dose to receive efficacy,” Dr.Sujal Mandavia, chief medical officer at Carbon Health, told Healthline.

This is because “the immune system of the fine layers of our skin is well primed to receive foreign things, like vaccines, and tends to respond quite vigorously.”

With vaccine shortages a challenge, the intradermal approach enables doses to be split into fifths. The result? “We can stretch the current available supply and vaccinate more at-risk individuals,” noted David M. Souleles, MPH, director of MPH Program and Practice at the University of California, Irvine.

However, Chang explained, it is recommended that those aged under 18 still receive the vaccination subcutaneously rather than intradermally.

If you only receive 20% of a typical monkeypox vaccine dose, you might think you wouldn’t be protected against the disease.

However, this isn’t the case according to the research.

The FDA made the decision to use a lower amount of vaccination and administer it intradermally “based on this clinical study involving 524 patients,” said Mandavia. “[The study] demonstrated that, when injected [intradermally] into the skin, one-fifth of the JYNNEOS vaccine produces a similar immune response to a ‘full’ dose of subcutaneous administration.”

While the current vaccination certainly offers protection, more research is needed into the defense levels it affords over an extended period. “The effect on long-term immunity and protection against monkeypox from the one-fifth intradermal dose remains unclear at this time,” Chang added.

Fortunately, receiving one-fifth of a vaccination dose doesn’t mean you need to have four follow-up injections to obtain optimum benefits.

“With intradermal administration of the monkeypox vaccine, two doses of the vaccine given 28 days apart is considered fully vaccinated and provides protection,” shared Souleles.

If you’re under the age of 18 and receive your vaccination subcutaneously, your second dose should also come 28 days after the first.

“Peak immunity is expected 14 days after the second dose of the JYNNEOS vaccine,” added Chang. “Unfortunately, second dose coverage is low per Centers for Disease Control (CDC) data.”

A key reason individuals are skipping their second dose? The appearance of a sore, red mark at the site of their first injection. Yet, this side effect isn’t limited to the monkeypox vaccine.

“This is a common issue with any intradermal injection, and not only the JYNNEOS vaccine,” Chang shared.

The reason this appears, Mandavia explained, is “because the body recognizes the viral load as foreign and sends immune cells to react against it.”

“Think about the COVID-19 vaccine or flu vaccine,” added Souleles. “That can often result in a sore arm at the injection site for days after the injection.”

While potentially unsightly and uncomfortable, “the red welt that commonly develops with the monkeypox vaccine is benign and is not harmful,” assured Mandavia.

For those concerned about developing another red mark in a visible area following the second dose, you have options. Chang explained it is possible to request the injection be given in a less visible “intradermal site, such as the shoulder (over the deltoid) or the upper back over the shoulder blades (scapula).”

Good news: Chang explained that the mark usually subsides “within 72 hours to 1 week” — although, in rare instances, they can remain for three to four weeks.

If, at any point following injection, “you develop worsening tenderness or swelling at the injection site, it is important to consult with a healthcare provider,” urged Chang.

In the meantime, if you develop a red mark at the injection point, following a couple of simple steps may help reduce it.

“Since this is typically related to skin irritation, gentle massage and applying a cold pack to the site can help relieve the symptoms faster,” Chang revealed.

Any damage to the skin (including via vaccination) can potentially leave a mark or scar in the long term. But some individuals are believed to be at greater risk.

For instance, it’s thought that those with keloids—or a history of them—are more likely to develop scarring following intradermal vaccination.

Keloids are excess growths of scar tissue that grow following ‘trauma’ to the skin. They are most often seen in those with darker skin, who are pregnant, or under the age of 30.

As such, the CDC recommends that individuals with keloids, either currently or previously, be given the monkeypox vaccination subcutaneously.

Additionally, the New York City Department of Health mentioned in their monkeypox vaccination leaflet, “that monkeypox infection has high potential for scarring and permanent skin changes.”

The Department for Health and Human Services renewed its declaration that the monkeypox outbreak is still a public health emergency.

The news comes as over 1 million people in the U.S. have received the monkeypox vaccine. Some people eligible for the monkeypox vaccine have brought up concerns about getting their second dose.

However, to obtain optimal protection against monkeypox, receiving the ‘full’ vaccination is essential. This means two injections, 28 days apart.

Having a sore mark “might be uncomfortable for a short time,” stated Mandavia. However, “it is a mild side effect of the vaccine that could save you from more serious illness with symptoms like a painful rash, fever, headache, muscle aches, backache, swollen lymph nodes, chills, and exhaustion.”

If you have any concerns about the vaccine, side effects, or potential scarring, always speak with your healthcare or vaccination provider.