Dozens of public health labs across the country now use a more widespread test for orthopoxvirus, a larger category that includes monkeypox, smallpox and other viruses. Two biotech companies, Roche and Abbott, have announced plans to implement monkeypox PCR testing, although right now, their testing kits are for research only.
The U.S. Centers for Disease Control and Prevention says it is exploring ways to get monkeypox-specific testing in states.
There are already 74 laboratories in 46 states, part of a network known as the Laboratory Response Network, that “use an FDA-approved test for orthopoxvirus,” CDC Director Dr. Rochelle Walensky said Thursday.
The current capacity is about 7,000 of these weekly tests, with the potential to expand if necessary.
Dr. Amesh Adalja, a senior researcher at the Johns Hopkins Center for Health Security at Bloomberg School of Public Health, said much of this capacity “was created in response to the threat of biological weapons, and the smallpox is the most worrying orthopoxvirus. ” “
The CDC’s tests are more specific to the monkeypox virus, and the agency can also genetically sequence samples. For example, it was by observing the viral genetic code of the first American patient, a Massachusetts man who had recently traveled to Canada, that researchers were able to see that his case of monkeypox closely matched that of a case in Portugal. .
However, Dr. Jennifer McQuiston, a veterinarian and deputy director of the CDC’s Division of Pathogens and High-Impact Pathology, stressed that the tests performed at the CDC are not really necessary for patient care.
“The orthopox test out there is an actionable test,” he said.
Experts say the action could include isolating patients, making treatments and vaccines available, and tracking contacts to determine who else might have been exposed to the virus.
Since other orthopoxviruses are not spreading to countries where they are not as endemic as the US, a positive test for orthopox here can be assumed to be indeed monkeypox, according to Adalja.
Countries like Spain have shifted to include positive orthopox cases as confirmed cases of monkeypox in their counts. CDC U.S. case tracking lists “confirmed total cases of smallpox / orthopoxviruses.”
“I think the more diagnostic tests closer to patients, the better. Commercial trials are even better,” Adalja said. “But the fact is that there are no other orthopoxviruses right now.”
He does not believe that the lack of specific evidence for monkeypox will make it difficult for the public health response “because a positive orthopox [case] it will be the monkey ‘s smallpox until proven otherwise in this scenario we are in now. “
He added that this is a very different situation from the stumble of Covid-19 testing in 2020, when the world was facing a new coronavirus without a major test alternative, which means it was often difficult. differentiate Covid-19 from other respiratory viruses such as. the flu. The smallpox of the monkey, on the other hand, has been known for decades and there is a plan.
“It’s not the same as Covid,” Adalja said.
Identification of smallpox smallpox
Smallpox is rare outside endemic countries and is not as transmissible as a virus such as Covid-19, according to the CDC. Humans can be infected by animals, but people can also become infected with each other through skin-to-skin contact; large respiratory drops, which tend to travel no more than a few feet; or contact with things contaminated by skin lesions, such as bedding.
Symptoms of monkeypox can include fever, headache, muscle aches, and swollen lymph nodes. A feature of the disease is a rash that causes lesions or pustules. This can happen to any part of the body, often to places such as the face, hands and feet. In the current outbreak, some cases have caused injuries to the genital area or groin, according to health authorities.
The process of identifying a case of monkeypox in the United States begins when a person notices possible symptoms and seeks medical attention. Your provider can contact a local or state health department to collect a sample for orthopox testing, said Chris Mangal, director of public health preparedness and response for the Public Health Laboratories Association.
At this time, the CDC recommends the collection of two specimens: swab lesions.
“When they do this test, and if the test is positive, they will report a positive presumption for non-smallpox orthopoxvirus. And that positive assumption is good enough, that combined with what you’re seeing in terms of patient. to give them the feeling that “we should take public health measures here,” Mangal said.
The second sample and test result are sent to the CDC for testing.
“The CDC and public health labs are working closely, hand in hand, on these tests,” Mangal said.
During the monkeypox outbreak, the process for confirmatory testing has been “good enough for the phase we are in now,” because there have not been a large number of cases, he said.
“If we put ourselves in the scenario where we are seeing a significantly larger number of cases of monkeypox, I think the CDC will work with the [US Food and Drug Administration] and public health labs to make sure they have that confirmatory capacity, ”he said, adding that there are some scenarios that could occur if that happened.
“We can have public health labs that develop their own tests developed by the lab,” Mangal said. “If this were to happen in an emergency scenario, similar to Covid, labs could work through the FDA to obtain an emergency use authorization for confirmatory testing.”
But in general, Mangal said, he does not see the current outbreak as a major emergency. For the general public, “it’s my opinion that they shouldn’t be too worried,” he said.
The current capacity for monkeypox testing “is not a major public health concern” in general, Adalja said, but there is still room for it to move faster or be more widely available.
“It would be great if Quest and LabCorp could do that. It would be great if there were kits that people could put in sexually transmitted infection clinics for definitive diagnosis,” he said. “But I don’t think you’re making the public health response difficult right now, just because there’s no other circulating orthopoxvirus.”
Even if the CDC transports monkeypox-specific tests to state public health labs, getting confirmatory results could take time, Adalja added.
“While we’re talking about state public health labs and members of the CDC’s Laboratory Response Network that can do orthodox PCR, it’s still a step: it still involves paperwork, it still involves making phone calls, which deters people from that, which has a built-in delay, “Adalja said.
“If you work at an ETS clinic in some city and you have this kit there, or you have a lab in your city that does it, that makes it a lot easier,” he said.
Plans for monkeypox PCR testing
Roche and Abbott’s planned PCR tests are separate from the CDC’s plans.
Neither has received a green light from the FDA, and both companies said last week that their tests are intended for “use of research,” although they are leaving the door open to address future testing needs.
Even if there is no need to expand testing to countries like the US, these moves could benefit other countries, including those in West and Central Africa, where the monkeypox virus has long been endemic.
“Some of the resource-poor countries where these diseases are endemic sometimes have a clearer path to getting these tests in people’s hands than in the United States, where there is so much regulation and it’s so hard to get tested to the point of attention, “Adalja said.
“I think there is an advantage to doing these tests in endemic countries so that people can get diagnoses quickly,” he added. “You can find outbreaks much faster. You can implement the smallpox vaccine faster for monkeypox.”