Monkeypox: What to Know About Vaccines, Tests and Treatment

The monkeypox outbreak continues to swell across the globe, leading the World Health Organization on Saturday to declare it a public health emergency of international concern. The designation means that a coordinated international response is needed to prevent the virus from spreading further and may push member countries to invest more funding in vaccines, treatments and other resources for curbing the disease.

Many of these critical tools are still not widely available, even in the United States. Public health messages around individual risk and access to care have not always been clear; the clinics doing testing and the health department officials who follow up with patients often lack coordination; vaccine distribution has lagged; and treatment options remain obscure.

To make things more complicated, monkeypox symptoms may look different in some cases. People who get sick do not always have the traditional fever, aches and body-wide rashes. Many patients have developed only a few pustules, primarily in the genital area. And according to health officials, the disease is primarily spreading in networks of men who have sex with men.

While prevention is still crucial, we asked experts to explain what steps you need to take to get vaccinated, tested and treated if you do suspect an infection or have recently been exposed to monkeypox.

Who is eligible for the vaccine? And where can you get it?

Two vaccines originally developed for smallpox and kept in the United States national stockpile can help prevent monkeypox infections. The one that is most commonly used for monkeypox is called Jynneos. It consists of two doses given four weeks apart. But because its supply is limited and is controlled by the federal government, it is not widely available to the public. Instead, the vaccine has largely been offered to two groups of people: health care or laboratory workers who might handle infected samples and people who have had a confirmed or suspected monkeypox exposure.

The vaccine can work even if given after someone is exposed, and the Centers for Disease Control and Prevention recommends that people get vaccinated within four days of the date of exposure for the best chance of preventing monkeypox. You can schedule an appointment for the vaccine through your local or state health department.

You can also get a shot up to two weeks after an exposure to help reduce symptoms, though a vaccination more than four days after an exposure may not prevent onset of the disease.

“You’d still need to take all the preventive measures for a few weeks after vaccination,” said Dr. Sharone Green, an infectious disease expert at the University of Massachusetts Chan Medical School in Worcester. Whether before or after exposure, individuals are generally considered fully protected two weeks after they have received their second dose, she said. However, some researchers have suggested that even a single dose of Jynneos may help slow the spread of monkeypox.

A few states where monkeypox case numbers are high have expanded their eligibility criteria for the vaccine to include anyone at high risk of getting it. For example, in New York and New Jersey, you can also get the vaccine if you attended an event where known monkeypox exposure occurred or if you identify as gay, bisexual, a man who has sex with other men, transgender, gender nonconforming or nonbinary and have had several sex partners, or anonymous partners, within the past 14 days. But it may be difficult to get an appointment for the vaccine because distribution has run into several roadblocks and delays.

When should you get tested?

Experts agree that vaccination and prevention should be prioritized to slow the pace of the current outbreak. But if you start to notice red lesions, pimples or pustules, you should contact your primary care physician and let the physician know that you suspect a monkeypox infection. Your doctor will swab a lesion and order a monkeypox test for you. You can also get tested at urgent care centers or sexual health clinics and through other health providers.

The test is a polymerase chain reaction, or P.C.R., much like those for Covid-19 that detect a piece of the virus’s genetic material. But testing capacity is still limited. Samples can be sent only to a public health laboratory or one of five commercial labs for analysis. And although the turnaround time has improved, results can take anywhere from 24 hours to three days or more.

There is no home test for monkeypox. And even at a clinic, health care workers need a lesion to swab in order to perform a monkeypox test, said Dr. William Morice, the chair of the department of lab medicine and pathology at Mayo Clinic and president of Mayo Clinic Laboratories, which developed one of the commercial monkeypox diagnostic tests. If you don’t have any symptoms, or have only fever and flulike symptoms, there is no way to test for monkeypox yet, Dr. Morice said.

Another problem is that some health…