Investigations into 2 E coli outbreaks end with sources still unknown

The Centers for Disease Control and Prevention (CDC) ended two separate Escherichia coli O157:H7 investigations on Dec 18. Neither of the outbreaks had a definitive source, although one triggered a food recall on a single brand of romaine lettuce.

A third E coli outbreak investigation, also caused by the O157:H7 strain, remains open, and hasn't had any new reported cases since Nov 23.

The first E coli outbreak had 32 cases, with illness onsets from Jun 6 through Oct 25, including 15 hospitalizations, 1 case of hemolytic uremic syndrome—a sometimes fatal kidney complication—and 1 death. The cases occurred across 12 states, with the most in California (10), Ohio (7), and Illinois (3). Infected people were between 2 and 75 years old, with a median age of 27.

The numbers reflect 11 new cases and 4 newly affected states since the CDC's previous update on Oct 18. Although several interviewed ill people said they ate multiple common food items at the same restaurant, investigators were not able to identify a common source.

Laboratory examinations of E coli samples from 15 ill people showed antibiotic resistance to chloramphenicol, streptomycin, sulfisoxazole, tetracycline, and trimethoprim-sulfamethoxazole, but the CDC notes that this does not affect E coli treatments.

The other closed E coli investigation (source 3) was associated with 18 cases and 6 hospitalizations across 9 states, with illness-onset dates ranging from Sep 2 to Nov 6. California-based Tanimura & Antle recalled its packaged single-head romaine lettuce Nov 6 because laboratory tests found the outbreak strain in a product sample; however, not all interviewed ill persons said they ate the product, and some people got sick before the "packed on" dates. Of the 13 people interviewed, all reported possibly eating leafy greens of some type. 

Ill people were from 8 to 71 years old, with a median age of 28, and cases were reported in nine states with the most in Illinois (4), California (3), and Michigan (3). Isolates from 16 ill people and four from food didn't show any antibiotic resistance. Since a Nov 11 CDC update, officials confirmed 6 new cases and 3 newly affected states.
Dec 18 CDC E coli update—source 1
Dec 18 CDC
E coli update—source 3


Variant H1N2 flu infects Brazilian child

Brazil has reported another variant H1N2 (H1N2v) influenza infection, its second of the year, according to a health ministry statement translated and posted by Avian Flu Diary (AFD), an infectious disease news blog.

The patient is a 4-year-old girl from Parana state in southern Brazil, the same state where swine H1N2v infected a 22-year-old woman in April. The girl's family took her to the hospital on Nov 16 for fever, respiratory problems, and other symptoms, and she is now being monitored at home. The ministry said the girl lived in the countryside, but it didn't say if she had been exposed to pigs.

Officials have reported the case to the World Health Organization (WHO) and the Pan American Health Organization.

Earlier this year, the WHO said 26 H1N2v cases have been reported since 2005, including 2 in Brazil. Most involved mild infections, and there was no evidence of person-to-person spread. The WHO also noted that most illness are related to swine exposure, and that more human infections are expected because the viruses continue to be reported globally in swine populations.
Dec 19 AFD post
Jul 10 CIDRAP News scan on previous case


China reports second H5N6 avian flu infection this month

China reported a new H5N6 avian flu infection, its second such case this month, Xinhua, China's state news agency, reported today. The report in Chinese was translated and posted by AFD.

The patient, who tested positive on Dec 19, is from Hunan province and is thought to have contracted the virus at a poultry trading market, which officials have temporarily closed. The patient is hospitalized and on a ventilator in the intensive care unit.

The country's earlier case involved an 81-year-old woman from Jiangsu province who died from her infection.

China's mainland has now reported 26 human H5N6 cases since 2014, 8 of them fatal. H5N6 outbreaks have been reported in poultry in China and a handful of other countries in Asia, but so far illnesses in humans have been reported only in China.
Dec 21 AFD post
Dec 17 CIDRAP News scan "Fatal H5N6 avian flu case reported in China"


HHS releases plan to decrease sexually transmitted infections

The Department of Health and Human Services last week released its first-ever plan to address sexually transmitted infections (STIs) in the United States.

The plan, which will serve as a roadmap for federal and non-federal stakeholders, aims to reverse a dramatic rise in STIs in recent years. From 2014 through 2018, reported cases of primary and secondary syphilis, congenital syphilis, gonorrhea, and chlamydia by 71%, 185%, 63%, and 19%, respectively. When left untreated, these infections can lead to a host of long-term health problems, including chronic pelvic pain, infertility, and poor birth outcomes, including death of newborns.

The plan establishes five goals, along with objectives, strategies, and targets to achieve those goals. New STI prevention is the primary goal, to be achieved in part through increased awareness of STIs and sexual health and an expanded sexual health workforce. The other goals include reducing adverse outcomes of STIs; accelerating progress in STI research, technology, and innovation; reducing STI-related health disparities and inequities; and achieving integrated and coordinated efforts to address the STI epidemic.

Using national-level data, HHS focuses the plan on three priority populations most disproportionately impacted by STIs: adolescents and young adults, men who have sex with men, and pregnant women. Within these populations, there will be additional focus on blacks, American Indian/Alaska Natives, and Hispanics and on southern and western regions of the country that have been most affected.

"The consequences of the STI epidemic are steep. When left untreated, STIs can lead to long-term, irreversible health outcomes affecting the quality of life for millions of Americans and costing the health care system billions of dollars annually," Assistant Secretary for Health Adm. Brett Giroir, MD, said in a press release. "The STI Plan provides an actionable roadmap to develop and implement programs at the national, state and local levels to help our nation stem and reverse the growing STI epidemic in the U.S."
Dec 17 HHS press release
Dec 17 STI National Strategic Plan 2021-2025

COVID-19 Scan for Dec 21, 2020

News brief

Higher pandemic death rate found in Hispanics, older adults, less educated

A study of pandemic deaths in California in JAMA Internal Medicine today found the highest excess mortality in older adults, black and Hispanic residents, and those without college degrees. Excess death rates for Hispanic residents and those without a high school degree more than tripled after reopening, likely due to increased COVID-19 risk faced by low-wage, essential workers.

Researchers evaluated mortality data across population subgroups in California from Mar 1 to Aug 22, finding 19,806 deaths in excess of those predicted by historical trends (95% prediction interval, 16,364 to 23,210). California has a population of 39 million, about 12% of the total US population.

Per capita excess mortality was highest among people aged 65 years and older, representing 66.5% of the total excess deaths in the state (13,187 out of 19,806 deaths). Black and Hispanic residents had higher per capita mortality than whites (1,206 and 922 per 1,000,000 people, respectively, vs 485 for whites).

Hispanic residents and those without a high school degree showed the greatest increases in excess deaths when comparing the Mar 1 through May 9 statewide shelter-in-place period versus the May 10 through Aug 22 reopening period. Excess deaths after reopening for Hispanic residents and those without a high school degree were more than triple those observed during the shutdown period (3.1- and 3.4-fold increases, respectively).

"Across age groups, younger adults had the greatest increases in excess death, with rates more than doubling between shutdown and reopening (age, 25-54 years: from 4 to 11 excess deaths per million, 55-64 years: from 12 to 30 excess deaths per million)," the authors wrote.

"We hypothesize that this pattern reflects the risk of COVID-19 death faced by low-wage, essential workers and their social networks owing to occupational exposure, crowded housing, and inadequate access to testing or treatments," they added.

"Our findings underscore the importance of examining the inequitable effects of policies during the pandemic, reexamining the effects over time, and investing in strategies to mitigate the excess mortality in affected communities."
Dec 21 JAMA Intern Med study


Pigs susceptible to SARS-CoV-2, researchers discover

In a study in Emerging Infectious Diseases late last week, Canadian and US researchers found that pigs are susceptible to SARS-CoV-2, the virus that causes COVID-19, highlighting the need for additional livestock assessment to determine the potential role of domestic animals in the pandemic.

Previous studies indicated that swine are not susceptible to SARS-CoV-2 infection, but they did not measure seroconversion (antibody production), the authors note.

They inoculated 19 8-week-old pigs (6 castrated males and 13 females) with an oronasal solution containing the SARS-CoV-2 virus, using a 10-fold higher infectious dose than that used in previous studies.

The researchers performed physical examinations and collected blood, rectal, oral, and nasal samples at the time of inoculation and every other day from day 3 until day 15. They evaluated samples for viral RNA using reverse-transcription polymerase chain reaction (RT-PCR) testing and tested blood serum for neutralizing antibodies. Necropsies and post-mortem sampling started at day 3 after inoculation and continued until day 29.

Starting at day 1, all of the pigs developed mild ocular discharge—accompanied by nasal secretion in some of the animals—which continued through day 3. Animal temperatures remained normal throughout the study, and none of the animals developed clinically observable respiratory distress, but one pig developed a mild cough lasting through day 4.

Among the 16 inoculated animals, 31.3% (5) displayed some level of exposure or an immune response to the virus. Only 1 pig—the animal that developed a mild cough—retained live virus, detected in a post-mortem sample of a lymph node. Two other animals had detectible RNA in a nasal wash sample, and two additional pigs had antibodies in blood serum. Among the five animals with potential infection, only low levels of viral RNA were detected, and no live viral shedding was identified.

Two control pigs were introduced to the infected pigs at day 10 to evaluate potential animal-to-animal transmission, but no viral infection occurred.

The authors conclude, "To date no SARS-CoV-2 cases among domestic livestock have been documented by natural infection; however, the results of this study support further investigations into the role that animals might play in the maintenance and spread of SARS-CoV-2."
Dec 18 Emerg Infect Dis study
Nov 17 CIDRAP News scan on COVID-19 in poultry

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