CAHFS Weekly Update: MN launches COVID-19 testing campaign for school going children; New Listeria outbreak linked to Queso Fresco Cheese; China: New African swine fever (ASF)
Sylvester Ochwo


Minnesota launches COVID-19 testing campaign for school going children

The Minnesota department of health (MDH) advises that all school-aged children and youth be screened for COVID-19 on a bi-weekly basis. This new focus for COVID-19 testing was announced on February 24th and is intended to target families, health professionals, schools and youth organizations. 

This announcement comes at a time when infection rates are in decline, and about 16% of the state’s population have been vaccinated against COVID-19, with the daily number of people taking the COVID-19 jab at a record high. The MDH advises that this testing campaign is meant to protect the progress made towards reducing new cases.

According to the MDH Assistant Commissioner Dan Huff, “The number of students taking in-person courses has grown sharply in recent months, with thousands more predicted to return in the coming weeks. This new congregation of people from different families might lead to a spike in new cases and jeopardize the advancement made towards slowing down COVID -19 infection rates. 

Assistant Commissioner Dan Huff further emphasized that “for as long as there are still cases in the state, testing will continue to be a critical part of our COVID-19 plan”.  “Our mitigation measures break down without adequate testing. Even as we continue to successfully vaccinate a growing number of people in our state, we also continue to expand our mitigation testing programs for childcare providers and educators.”

The state of Minnesota has set up free community testing centers for families. To find a free community testing location go to the Minnesota COVID-19 website.

Minnesota Department of Health


New Listeria outbreak linked to Queso Fresco Cheese 

The centers for disease control (CDC) and the U.S. Food and Drug Administration (FDA) have reported a new outbreak of Listeria associated with Hispanic styled fresh and soft cheeses.  According to the CDC, as of March 01, 2021, four states (Connecticut, Maryland, New York and Virginia) have reported a total of eleven people infected with the outbreak strain of Listeria Monocytogenes. Ten of the eleven people were hospitalized while a single death has been reported in Maryland. 

This is the latest Listeria outbreak and it is reported to have started at the end of last year (October 2020); previous outbreaks have been linked to contaminated deli meats and enoki mushrooms. 

Listeriosis is a bacterial infection caused by eating Listeria monocytogenes-contaminated food. The CDC reports that nearly 1,600 persons develop listeriosis each year, with about 260 dying as a result of infection. 

The CDC says the actual number of people infected in an epidemic is almost always higher than the number reported, and the outbreak might not be confined to states where illnesses have been confirmed, since certain people recover without medical treatment and are not screened for Listeria. Furthermore, new infections may not have been identified yet, since assessing whether a sick person is part of an outbreak usually takes 2 to 4 weeks.

In the meantime, public health actions have been taken by the FDA and as a result El Abuelito Cheese Inc.  have recalled cheese products including all quesillo and requeson products that were made or packed at the same facility as the contaminated queso fresco. The general public have been advised against eating, selling or serving recalled queso fresco, quesillo, or requeson cheeses.



China: New African swine fever (ASF) variants could complicate disease control

New variants of African swine fever have been reported to be circulating in China. While these ASF variants cause a less virulent type of disease, they are more difficult to detect, making disease prevention attempts more difficult. China is currently emerging from the crippling impact of the 2019 outbreaks of ASF, which decimated 40% of the country's pig population.

These new ASF variants are believed to be vaccine strain viruses. Dr. Wayne Johnson, a Consultant pig veterinarian in China, says “The ‘new virus’ circulating in China is most likely linked to illegal double-gene deleted vaccine virus. It lacks safety and its efficacy is not clear. This vaccine has deletions in the MGF360 locus and the CD2v locus which weakens the virus but does not render it innocuous. It just produces a milder form of the disease,”

While it's common for viruses to mutate spontaneously, Dr. Johnson doesn't believe that's what happened in China. When speaking to Pig Progress, he said that the mutation was deliberately introduced into a substantial portion of China’s pig population through the use of Illegal vaccines. 

However, in a separate study published, just recently, by scientists at the Harbin Veterinary Institute,  new ASF variants with naturally occurring mutations were detected during a six-month surveillance exercise. Two (2) of the 22 viruses isolated and characterized showed low virulence but high transmissibility. Currently, there is still no cure or approved vaccine for ASF in the world, but Illegal ASF vaccines have been reported to be produced and used in China.

It will be important for the regional neighbors to monitor the spread of these new genes deleted virus strains, since they may further complicate control efforts of a disease that has already greatly affected the pig industry in Asia.

The Pig Site
The Telegraph UK


Sylvester Ochwo

Sylvester has been a researcher at the College of Veterinary Medicine Animal Resources and Biosecurity (COVAB), Makerere University for the last 10 years. He has substantial experience in epidemiology and laboratory diagnosis of infectious diseases, especially transboundary animal diseases of livestock. While at Makerere University, Sylvester was also an instructor for both undergraduate and graduate students at the College of Veterinary Medicine.

He is particularly interested in understanding the drivers and patterns of spread of OIE-notifiable animal diseases; foot-and-mouth disease, African swine fever, lumpy skin disease and peste des petits ruminants, which greatly affect livelihoods in developing nations. Sylvester attained his PhD in Veterinary Epidemiology from Makerere University. He also holds MS and BS degrees from the same University.