Small, deadly outbreak of Rocky Mountain spotted fever tied to city in Mexico, CDC says

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Brown dog tick
The brown dog tick, which transmits the disease.
Ingeborg van Leeuwen / Flickr cc

At least five people have contracted the tick-borne disease called Rocky Mountain spotted fever (RMSF) after travel to Mexico, and three died, the US Centers for Disease control and Prevention (CDC) said in a Health Alert Network advisory late last week.

All the patients—four of whom are children—were treated at hospitals in Southern California after travel to Tecate, a city in Baja California, which is a Mexican state south of California. The CDC noted that RMSF is a rapidly progressive disease and can be fatal within days without early administration of the antibiotic doxycycline.

Early treatment essential

The CDC said, "Consider initiating doxycycline based on presumptive clinical and epidemiologic findings, and do not delay treatment pending the result of a confirmatory laboratory test. Early treatment with doxycycline saves lives."

The patients were diagnosed as having lab-confirmed RMSF since late July. All had traveled to or had lived in Tecate within 2 weeks of illness onset. The disease is endemic in multiple border states in northern Mexico. Three patients were US residents, and two were Mexicans. All five were hospitalized, and three died.

Early treatment with doxycycline saves lives.

The bacterium that causes RMSF, Rickettsia rickettsii, can be transmitted by brown dog ticks (Rhipicephalus sanguineus), which feed on dogs in and around cities in some regions. The CDC said many people who have the disease don't recall a tick bite.

RMSF signs and symptoms can be relatively mild and not very specific during the first 1 to 4 days of illness and include a low to moderate fever, headache, gastrointestinal symptoms, abdominal pain, muscle aches, rash, and swelling around the eyes and on the back of hands. Patients with more advanced disease may experience altered mental state, coma, brain swelling, difficulty breathing, and multiorgan system damage. The case-fatality rate of RMSF in Mexico can exceed 40%, the CDC said.

Study suggests race, ethnicity should be considerations in antibiotic stewardship

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An outpatient antibiotic stewardship intervention implemented across a US urgent-care network was associated with reduced antibiotic prescription for respiratory encounters for all patients regardless of race, ethnicity, or preferred language, but disparities between groups remained, researchers reported today in Infection Control & Hospital Epidemiology.

Nurse speaking with patient
Michael Jung / iStock

The stewardship intervention implemented at Intermountain Healthcare, which has urgent care facilities at hospitals in Utah and Colorado, included electronic health records tools, a transparent clinician benchmarking dashboard, and English- and Spanish-language education focused on urgent-care clinicians and patients. Although health equity was not explicitly considered when the intervention was designed, researchers at Intermountain Healthcare sought to determine if its effect differed by patient race, ethnicity, or preferred language.

Comparing the 12-month baseline period (July 2018 to June 2019) with the intervention period (July 2019 to June 2020), the researchers found that all evaluated race, ethnicity, and preferred language categories saw reductions in respiratory antibiotic prescribing. An interrupted time series analysis found no difference in the impact of the intervention between studied groups: White people (odds ratio [OR], 0.95; 95% confidence interval [CI], 0.94 to 0.96) versus non-White people (OR, 0.95; 95% CI, 0.94 to 0.96); non-Hispanic ethnicity (OR, 0.95; 95% CI, 0.94 to 0.96) versus Hispanic (OR, 0.95; 95% CI, 0.93 to 0.97); and those who preferred speaking English (OR, 0.95; 95% CI, 0.94 to 0.96) versus those who preferred Spanish (OR, 0.95; 95% CI, 0.90 to 0.99).

Prescribing disparities persist

The analysis, however, also found that differences in antibiotic prescribing between groups persisted over the course of the study, with higher proportions of White, non-Hispanic, and English-speaking patients receiving antibiotics. The study authors say that while they were not aware of these disparities when they designed the intervention, they have since integrated patient race, ethnicity, and preferred language into their antibiotic prescribing dashboard.

"Our experience highlights the importance of not only examining interventions via factors related to health equity such as race, ethnicity, and language but also the need to design interventions that address the needs of all patient populations, especially those historically marginalized in healthcare delivery," they wrote.

Obesity tied to COVID-related inflammatory syndrome, poor outcomes in kids

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Obese child
Iuliia Burmistrova / iStock

Obesity is more common in patients diagnosed as having COVID-related multisystem inflammatory syndrome in children (MIS-C) than those with Kawasaki disease (KD) and is tied to worse outcomes, suggests a study published late last week in JAMA Network Open.

A University of Alberta researcher led the study of 1,767 KD and MIS-C patients at 42 sites in eight countries from January 2020 to July 2022. Of 1,767 children, 338 had KD (median age, 2.5 years; 60.4% boys), and 1,429 had MIS-C (median age, 8.7 years; 61.4% boys).

KD inflames blood vessels and can lead to long-term complications and death. MIS-C is a systemic inflammatory disease characterized by heart abnormalities that usually resolve within weeks, the authors noted.

Obesity not associated with KD outcomes

The prevalence of overweight and obesity was significantly higher in MIS-C than KD (41% vs 23%). Rates of overweight (17.1% vs 11.5%) and obesity (23.7% vs 11.5%) were significantly higher in MIS-C than KD, even after adjustment for age, sex, and race.

For KD, higher adiposity (overweight) categories weren't tied to lab results or disease outcomes, except for intensive care unit (ICU) admissions.

The findings of this study suggest that obesity is a comorbid factor that should be considered at the clinical presentation in children with MIS-C.

For MIS-C, higher adiposity was associated with worse lab test results and outcomes, including a greater likelihood of shock, ICU admissions, and need for inotropic drugs to strengthen heart contractions, as well as higher concentrations of inflammatory biomarkers and levels of creatinine (measure of kidney health) and alanine aminotransferase (measure of liver health).

"The findings of this study suggest that obesity is a comorbid factor that should be considered at the clinical presentation in children with MIS-C," the researchers wrote.

In a related commentary, Kirsten Dummer, MD, and Jane Burns, MD, both of the University of California San Diego, said obesity is difficult to disentangle from social determinants of health and variant exposure. "Given the global decrease in MIS-C case numbers, the data presented by Khoury and colleaguesmay be the final word on the possible role of obesity in influencing clinical disease severity in MIS-C."

Chronic wasting disease detected in another Texas county

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Young white-tailed deer
Larry Smith / Flickr cc

Chronic wasting disease (CWD) has been detected for the first time in Coleman County, Texas.

In a news release, the Texas Parks and Wildlife Department (TPWD) late last week confirmed a CWD case in a 2-year-old whitetail buck harvested by a hunter on a low-fenced property and tested through surveillance sampling. The TPWD said it will establish CWD containment and surveillance zones in the area this year or next.

In Texas, the disease was first discovered in 2012 in free-ranging mule deer along a remote area of the Hueco Mountains near the border with New Mexico, the release said. Since then, it has been detected in state captive and free-ranging cervids, including white-tailed deer, mule deer, red deer, and elk.

CWD is a fatal neurologic disease caused by infectious misfolded proteins called prions. While the disease is not known to infect humans or other non-cervid animals, experts fear it could jump species.

H5N1 avian flu kills almost 1,000 seals and sea lions in Brazil

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3 sea lions
Linda De Volder / Flickr cc

Brazil's southernmost state of Rio Grande do Sul today confirmed that highly pathogenic H5N1 avian flu was involved in the deaths of 942 seals and sea lions, while the United States reported more outbreaks of the virus in domestic birds.

Oceanographer Silvina Botta, PhD, at the Rio Grande Federal University, told Reuters that the mammals' carcasses have to be buried or incinerated as soon as possible to reduce the risk of spreading the disease to birds, other animals, or people.

Scientists have also found some sea mammals convulsing on local beaches as the H5N1 strain attacks their nervous system. Under government regulations, animals need to be euthanized to spare them "a very painful death," Botta said. She added that the virus first started killing sea mammals in Brazil in September, and three towns in the state still have active outbreaks.

High-path H5N1 was first detected in Brazil in mid-May.

H5N1 on farms, small flocks in 10 US states

In the United States, the US Department of Agriculture Animal and Plant Health Inspection Service has confirmed multiple H5N1 avian flu outbreaks in 10 states that affect chicken, turkey, and duck farms plus backyard flocks.

The largest outbreak involved more than 2.6 million egg-laying chickens on a farm in Hardin County, Ohio. That state also reported H5N1 on a turkey farm in Darke County. Other states reporting turkey outbreaks are Arkansas (Carroll County), Minnesota (Becker and Todd counties), South Dakota (Bon Homme, Charles Mix, and Hamlin counties), and Wisconsin (Barron County).

California confirmed an H5N1 outbreak at a farm housing 270,000 laying chickens in Sonoma County and a farm housing 258,600 broiler chickens in Stanislaus County, as well as an outbreak affecting 4,900 farm ducks in Sonoma County.

Officials in Iowa, Kansas, Michigan, and Vermont confirmed the virus in small flocks.

Zambia reports 684 suspected anthrax cases, 4 deaths

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Dead hippo
Mike W. / Flickr cc

Zambia is reporting by far its most widespread anthrax outbreak ever, with 684 suspected cases and 4 deaths, the World Health Organization (WHO) reported late last week.

Cases have been reported in 9 of Zambia's 10 provinces. Previous outbreaks were confined to Northwest and Western provinces, with sporadic cases over the years. "Of note," the WHO said, "Zambia reported anthrax outbreaks in both human and animals in Western Province in 2017 and in Eastern Province in 2016 and 2011." The 2011 outbreak involved 511 suspected cases.

First patients ate meat from dead hippos

The outbreak began in June in Sinazongwe district in Southern province. Twenty-six people developed sores on their face, arms, and fingers after eating meat from three wild hippopotamus carcasses. Around the same time, cattle, goats, and hippos were reportedly dying from an unknown cause in surrounding areas.

Sinazongwe district remains the outbreak epicenter, accounting for 287 cases (42% of the total) and 2 deaths.

The risk of anthrax transmission to neighbouring countries is increased.

Anthrax is a zoonotic disease caused by the bacterium Bacillus anthracis that typically affects ruminants like cows, sheep, and goats. The bacteria produce extremely potent toxins, and people can develop the disease by contact with infected animals or contaminated animal products.

The WHO said, "The epidemic is spreading along the provinces located along the basin of the Zambezi, Kafue, and Luangwa rivers, which is an additional problem because these rivers also flow into Lake Kariba in Zimbabwe, Kahora Bassa in Mozambique and Lake Malawi, and the risk of anthrax transmission to neighbouring countries is increased."

Sexually transmitted infections climbing in Europe

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New data from Europe show a sharp increase in sexually transmitted infections, according to surveillance reports published late last week by the European Centre for Disease Prevention and Control (ECDC).

The surveillance reports on gonorrhea, chlamydia, syphilis, congenital syphilis, and lymphogranuloma venereum (LGV) "collectively reveal a dynamic and challenging landscape," the ECDC said in a press release.

Following a drop in the first year of the COVID-19 pandemic, there were 46,728 confirmed cases of gonorrhea across 27 European Union/European Economic Area (EU/EEA) countries in 2021, with an overall crude notification rate of 13.7 cases per 100,000 population—higher than observed in 2019. In addition, the proportion of gonococcal isolates with resistance to azithromycin—one of the last remaining recommended antibiotics for gonorrhea—rose from 3.7% in 2017 to 14.1% in 2021.

The reports on chlamydia and syphilis showed similar trends, with dips in 2020 followed by increases in 2021. There were 184,542 and 25,270 confirmed cases of chlamydia and syphilis in 2021, respectively. Congenital syphilis cases fell in 2020 and 2021 following a peak in notifications in 2019.

Altogether, these reports signal a critical juncture in the battle against STIs in Europe.

While men who have sex with men (MSM) accounted for more than half of reported gonorrhea cases and 77% of syphilis cases, rates of chlamydia were highest among young adult heterosexual women.

The ECDC also reported a sharp rise in the incidence of LGV, an infection that's caused by the same bacterium that causes chlamydia (Chlamydia trachomatis) but has potentially long-lasting consequences. The ECDC notes the number of cases reported is likely an underestimation since many EU/EEA countries don't have surveillance systems for LGV.

'Collaborative efforts' needed

The ECDC said enhanced prevention activities that focus on increased testing, targeted messaging, and tailored interventions are crucial, and that ongoing monitoring of antimicrobial resistance is "imperative" for informing treatment strategies and addressing emerging challenges.

"Altogether, these reports signal a critical juncture in the battle against STIs in Europe," the agency said. "Collaborative efforts among public health authorities, healthcare providers, and communities are essential to curb the spread of these infections."

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