A preferred vaccine and antiviral in pregnancy
One monkeypox vaccine, Jynneos, is preferred for use during pregnancy, while another, ACAM2000, is contraindicated, the CDC advises.
Jynneos can be offered to people who are pregnant or breastfeeding who are eligible for vaccination based on confirmed or likely contact with cases, ideally within 4 days of exposure. People at high risk for exposure, such as laboratory workers, may receive the vaccine in advance.
Developmental toxicity studies in animals showed no evidence of harm with the Jynneos vaccine, Dr. Jamieson said.
ACAM2000, however, can cause fetal vaccinia and should not be used in people who are pregnant or breastfeeding, according to the CDC.
The Society for Maternal-Fetal Medicine notes that, if treatment for monkeypox is warranted, tecovirimat should be considered the first-line antiviral for pregnant, recently pregnant, and breastfeeding people, in line with CDC guidance.
Current outbreak ‘very different,’ but lessons apply
In 2003, some women exposed to monkeypox through contact with infected prairie dogs were pregnant – which is how Dr. Jamieson came to be involved in responding to the outbreak and studying the effects of the virus in pregnancy.
“When this resurfaced this year, of course it caught my attention,” Dr. Jamieson said. The extensive person-to-person transmission and far greater number of cases today make the current outbreak “very different” from the prior one, she said.
But key principles in managing the disease and understanding its potential risks in pregnancy – despite relatively limited information – remain the same.
“Whenever you are looking at an infectious disease, you want to think about, are pregnant persons more susceptible or more likely to have severe disease,” Dr. Jamieson said. Smallpox, a similar orthopoxvirus, “is more severe during pregnancy with a higher case fatality rate,” which is one reason for concern with monkeypox in this population.
In terms of pregnancy outcomes, researchers have data from only a handful of confirmed cases of monkeypox, which makes it difficult to draw conclusions, Dr. Jamieson said. A review of five cases from outside the United States in prior years found that three resulted in loss of the pregnancy. One resulted in preterm delivery of an infant who subsequently died. One child was apparently healthy and born at term.
Addition to the differential diagnosis
A separate team of researchers has proposed a clinical management algorithm for pregnant women with suspected exposure to monkeypox.
“Clinicians must maintain a high index of suspicion for monkeypox virus in any pregnant woman presenting with lymphadenopathy and vesiculopustular rash – including rash localized to the genital or perianal region – even if there are no apparent epidemiological links,” Pradip Dashraath, MBBS, National University Hospital, Singapore, and coauthors wrote in The Lancet.
Jamieson echoed the call for increased vigilance.
“As ob.gyns., people may present to us with genital lesions concerning for sexually transmitted infection. And it is important to include monkeypox in our differential,” Dr. Jamieson said. “We are trying to get the word out that it needs to be part of what you think about when you see a patient with genital ulcers.”
Health care professionals have acquired monkeypox through contact with patients or fomites, so clinicians should be sure to use appropriate precautions when evaluating patients who might have monkeypox, Dr. Jamieson added. Appropriate protective measures include wearing a gown, gloves, eye protection, and an N95.
A version of this article first appeared on Medscape.com.