The US Centers for Disease Control and Prevention (CDC) yesterday said it has received reports of 90 imported Oropouche virus from 5 states, mostly from Florida, and it also issued recommendations for male travelers to prevent possible sexual spread. 

The group has warned about the risk of infected pregnant women passing the virus to their fetuses and the possibility of poor fetal outcomes. In its latest update, the CDC also acknowledged the risk of sexual transmission, raised in a recent scientific report, but said no sexual transmission cases have been reported. 

In new interim recommendations to prevent sexual spread for travelers to affected areas, the CDC recommends that men diagnosed with Oropouche infections use condoms or abstain from sex for 6 weeks from the start of symptoms.

For those with Oropouche symptoms during travel or within 2 weeks of travel, the CDC recommends talking to a healthcare provider about testing or consider using condoms or abstaining from sex for 6 weeks since the start of symptoms.

For those planning to donate semen, the CDC said that until more is known, men who have Oropouche symptoms should wait 6 weeks before donating. Those who were potentially exposed during travel should consider waiting 6 weeks after returning from travel to donate.

Ecuador and Guyana report first Oropouche virus cases

Two new countries in the Americas region—Ecuador and Guyana—have reported their first locally acquired Oropouche virus cases, the Pan American Health Organization (PAHO) said in its monthly update. 

Since the group’s last update in September, 423 new cases have been reported from 7 countries. The majority were from Brazil, followed by Cuba, which has also reported three cases of Guillain-Barre syndrome linked to the disease. The United States reported 69 imported cases. 

Since the first of the year, 10,275 cases of Oropouche virus, spread by some midge and mosquito species, have been reported from 9 countries. Severe fetal outcomes, including fetal death and congenital malformation, have been reported from Brazil and Cuba. 

Los Angeles County, California, yesterday reported two more locally acquired dengue infections that are part of a cluster of cases from Baldwin Park, for a total of five since September 9.

A case in Panorama City, located about 40 miles west of Baldwin Park, reported on September 25 and two cases in El Monte earlier in October aren't considered related to the Baldwin cluster. None of the affected patients had a history of travel to tropical regions endemic for the mosquito-borne virus.

"This small local outbreak raises concerns about the ongoing spread of dengue and the potential for spread to other areas of LA County," LA Public Health said on X. "Everyone in LA County should take action to prevent mosquito bites and mosquito breeding."

On October 6, San Diego County announced the detection of locally acquired dengue in an Escondido resident. Pasadena and Long Beach, California, each reported one such case in fall 2023.

Mosquito avoidance urged

In the press release, Muntu Davis, MD, MPH, Los Angeles County health officer, said mosquito-bite prevention "can be as simple as using insect repellent to prevent mosquito bites, eliminating any standing water around your home where mosquitoes can breed, and keeping your home mosquito-free by using or fixing screens on your doors and windows."

This small local outbreak raises concerns about the ongoing spread of dengue and the potential for spread to other areas of LA County.

Dengue fever typically causes no symptoms but may lead to high fever, severe headache, pain behind the eyes, joint and muscle pain, rash, and slight bleeding. In about 1 in 20 infections, it results in shock, severe bleeding, and organ damage. While no antiviral drug is available to treat dengue, there is a vaccine, but it is not approved for use in US travelers visiting but not living in an endemic area.

Rwandan scientists and partners from the World Health Organization (WHO) have launched the world’s first clinical trials for Marburg virus disease treatment. Currently, there are no approved treatments or vaccines against Marburg virus, though a clinical trial of an investigational Marburg virus vaccine from the Sabin Vaccine Institute recently launched in the country. 

Matshidiso Moeti, MBBS, head of the WHO Africa regional office, said on X today that the clinical trial will test the efficacy and safety of remdesivir as well as MBP091, a monoclonal antibody that targets Marburg virus. The drug was developed by Mapp Biopharmaceutical with support from the Biomedical Advanced Research and Development Authority (BARDA), which is part of the US Department of Health and Human Services (HHS) Administration for Strategic Preparedness and Response (ASPR).

Health ministry reports no new cases or deaths

For the third day in a row, Rwanda’s health ministry reported no new Marburg cases or deaths, keeping the outbreak total at 62 infections, 15 of them fatal. Since the outbreak was first announced, all new cases have been related to a hospital cluster and their contacts in Kigali. Officials said there is no evidence of community spread.

Eight more people recovered from their illnesses. Health workers have also vaccinated 856 people as part of the clinical trial of the Sabin Vaccine Institute’s investigational Marburg virus vaccine.

The Michigan Department of Agriculture and Rural Development (MDARD) today announced another avian flu outbreak in dairy cattle, its first since early September.

The state’s latest outbreak occurred at a farm in Clinton County, which is near Lansing. Michigan has now reported 30 outbreaks in dairy cattle.

Testing at the Michigan State University Veterinary Diagnostic Laboratory initially identified the virus, and samples will be sent for confirmation testing to the US Department of Agriculture (USDA) National Veterinary Services Laboratory.

If confirmed as H5N1, the detection would push the number of US outbreaks in dairy cattle to 306 from 14 states.

USDA confirms more detections in Florida dolphins

In other avian flu developments, the USDA’s Animal and Plant Health Inspection Service has confirmed three more H5N1 detections in bottlenose dolphins, which were sampled last December and January. All involved animals are from Brevard County.

The H5N1 detections in US dolphins are the first since 2022, when the virus was found in a bottlenose from Florida’s Dixie County. The clade 2.3.4.4b H5N1 virus is known to infect sea mammals, including seals and sea lions, among several other mammal species.