As the number of global smallpox cases rises above 1,300, we are getting a clearer picture of how the infection is playing out for individuals. For the most part, it’s been quite manageable: Affected people have clusters of small, painful bumps or blisters — usually in the genital area after sexual contact — that are accompanied by fever and swollen lymph nodes. Often, the rash spreads to the arms, legs, and face.
While monkeypox is known to leave scars that can cause cosmetic problems, the less virulent version of the West African virus circulating today is rarely lethal. As of June 2, none of the people involved in the current outbreak have died, in countries where the disease is not endemic.
Also, it is relatively easy to avoid an infection. The virus usually spreads through contact with a smallpox sore, so not touching other people’s rashes is a solid prevention strategy.
With monkeypox infections preventable and not particularly deadly, it can be easy to eliminate the threat of this pathogen. But we shouldn’t, and for one important reason: these infections can kill.
As Covid-19 has made clear, one person’s mild infection can be another’s death sentence. A minority of people are more at risk due to pre-existing conditions – and as the outbreak grows, so does the likelihood that smallpox will find more vulnerable individuals. That makes it a pathogen worth containing – and worth having and sharing good treatments. It’s also worth finding out who is most likely to be hurt the most as the outbreak continues to spread.
The risk of complications from monkeypox is greater for people who are immunocompromised, pregnant or with certain skin conditions.
Our best understanding of the range of problems smallpox can cause comes from Nigeria, where healthcare workers have identified more than 550 smallpox cases since an outbreak broke out there in 2017.
The rash that most people get from smallpox infection can be extremely painful, in some cases requiring hospitalization just to control the discomfort the bumps and blisters can cause. But what makes monkeypox dangerous is when the virus spreads to organ systems beyond the skin, said Andrea McCollum, an epidemiologist in the smallpox and rabies branch of the Centers for Disease Control.
In cases where monkeypox infection led to death, patients suffered severe infections in the brain, bloodstream, or lungs. These complications may have resulted from direct viral effects on organs or from bacterial infections that the inflammatory effects of the virus helped to facilitate, often called “secondary” infections.
These complications are more likely among people with severe immunosuppression, according to Dimie Ogoina, an infectious disease physician at Niger Delta University in Bayelsa, Nigeria, and lead author of a report describing outcomes among Nigerian patients hospitalized between 2017 and 2018. .
Since the outbreak in Nigeria began, nine people have died from smallpox infections, he explained in an email. Four of the people who died were living with uncontrolled HIV infection, Ogoina said, while one was a newborn and another had underlying kidney disease and was taking immunosuppressive drugs. Additionally, a pregnant woman with monkeypox had a miscarriage of her pregnancy at 26 weeks’ gestation.
It’s not entirely clear why certain immunocompromised states put people at greater risk for complications from monkeypox, said Stuart Isaacs, a virologist at the University of Pennsylvania who studies poxviruses, the family that includes the monkeypox virus.
The researchers tried to clarify the exact types of immunocompromised states that increase poxvirus risks using animal models. These experiments showed that CD4 T cells (which are depleted by untreated HIV infections) and antibody-producing B cells play an important role in controlling the initial infection. However, there is currently little human data to go on, said Brett Petersen, an internist and medical epidemiologist at the CDC.
For now, the agency’s treatment recommendations currently suggest that people with a wide range of immunocompromised conditions are at risk for serious illness (including HIV, a variety of cancers, organ transplants, certain stem cell transplants, and certain autoimmune diseases). , as well as children. under eight years of age.
People with pre-existing skin conditions such as eczema (i.e., atopic dermatitis) are also at greater risk, McCollum said, possibly because people spread the infection from one place on their body to another by scratching, and pregnant women, who have more likely to spread the virus. to their pregnancies and potentially causing miscarriage.
Risk factors for monkeypox infection outweigh risk factors for a key immunocompromised state: uncontrolled HIV
In the current global outbreak, monkeypox appears to be spreading largely through the kind of close contact that takes place during sex. The same types of contact that put people at risk for monkeypox also put them at risk for uncontrolled HIV infections. And this raises concern that people with uncontrolled HIV are at the greatest risk, not only of becoming infected with monkeypox, but of suffering its worst consequences.
“That’s what worries me the most,” said Gregg Gonsalves, an epidemiologist at the Yale University School of Public Health and an HIV and global health activist. On average, 13% of Americans with HIV are unaware of their diagnosis and are not on treatment, but that proportion is as high as 20% in some southern states and even higher in several lowland and western states. “If there’s a fifth of the HIV-positive community that doesn’t know their status, it means they’re at risk,” said Gonsalves.
A disease transmitted during sex can be contained if people avoid sexual contact when they are sick or strictly use precautions such as condoms or dental dams. And while many sexually active people use these precautions, people whose sexual activity is stigmatized — such as closeted gay or bisexual men — are less likely to do so. For these groups, homophobia and other stigmas often interfere with getting tested and seeking care for sexually transmitted infections, including HIV.
This means that the same marginalized people who are at greatest risk of untreated HIV are at greatest risk of monkeypox infections – and for serious consequences of both. In many parts of the US, homophobia disproportionately prevents black men from receiving life-saving HIV treatment – a major contributor to higher rates of HIV infections and deaths among black Americans.
The more the outbreak spreads, the more likely it is to eventually reach a greater number of immunocompromised people, where it can lead to dire consequences. This should drive us to urgent action, regardless of where the spread is taking place, Ogoina said.
“If global action is not taken to better understand the virus and disease everywhere and develop innovative countermeasures to address the challenge of smallpox everywhere,” Ogoina wrote, there is a serious risk. So we could see big changes in who the virus infects and how much damage it does.