Prompt and Intensive #Antiviral #Chemoprophylaxis in Nursing Home #Influenza #Outbreaks

 

Key Points

-- Question:  Is initiation of antiviral chemoprophylaxis with oseltamivir for 70% or more of eligible nursing home (NH) residents within 2 days of outbreak detection associated with lower 14-day and 30-day mortality and hospitalization compared with a nonintensive approach?

-- Findings:  In this cohort study of 404 influenza outbreaks across 318 NHs with 35 086 resident-trial observations using a sequential target trial emulation and the randomize-censor-weight approach, hospitalization but not death was lower at 14 days post outbreak in NHs that implemented intensive antiviral chemoprophylaxis; 30-day estimates were directionally similar but less precise.

-- Meaning:  Results of this study suggest that clinicians should promptly initiate antiviral chemoprophylaxis in at least 70% of NH residents within 2 days of an influenza outbreak to markedly reduce influenza-related hospitalizations.

Abstract

Importance  

Influenza outbreaks in nursing homes (NHs) can cause high morbidity and mortality. Antiviral chemoprophylaxis with oseltamivir is recommended, yet optimal implementation strategies remain unclear.

Objective  

To examine whether initiating antiviral chemoprophylaxis for 70% or more of eligible NH residents within 2 days of influenza outbreak detection is associated with lower all-cause mortality and hospitalization at 14 and 30 days.

Design, Setting, and Participants  

Retrospective cohort study using a sequential cluster-randomized target trial emulation and randomize-censor-weight approach for influenza outbreaks (September 1, 2018–May 31, 2022) in 12 US NH corporations. Eligibility criteria were age 18 years or older, present on the outbreak-detection day, no antiviral use in the preceding 7 days, no influenza in the past 14 days, and complete baseline data. Residents were followed up until hospitalization or death, an NH discharge to a nonacute-care location, or the end of follow-up. Data were analyzed from February 2023 to January 2026.

Exposures  

Intensive antiviral chemoprophylaxis with oseltamivir (≥70% of eligible residents within 2 days of outbreak detection) or nonintensive antiviral chemoprophylaxis (0% to <70% of eligible residents).

Main Outcomes and Measures  

Outcomes were all-cause death and hospitalizations within 14 and 30 days of outbreak detection. Discrete-time hazard models with pooled logistic regression were applied to estimate weighted risks, risk differences (RDs), and risk ratios (RRs).

Results  

Among 404 outbreaks in 318 NHs, 35 086 resident-trial observations (29 683 residents; median age 78 [IQR, 68- 86] years; 60% women; 81% White; 76% vaccinated) met eligibility criteria. Intensive oseltamivir prophylaxis was randomized to 17 155 observations; 17 931 were randomized to nonintensive care. At 14 days, intensive prophylaxis vs nonintensive yielded an RD of –0.06% (95% CI, −0.73% to 0.93%) and an RR of 0.96 (95% CI, 0.56-1.57) for death, and an RD of –0.96% (95% CI, −1.78% to −0.19%) and an RR of 0.79 (95% CI, 0.64-0.96) for hospitalization. At 30 days, the hospitalization differences persisted but were less precise and there continued to be no difference in death.

Conclusions and Relevance  

Study results suggest that clinicians should initiate antiviral chemoprophylaxis for at least 70% of eligible NH residents within 2 days of outbreak detection to lower risk of hospitalization.

Source: 

Link: https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2846967

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Limited durability of #improvements in #infection #prevention and control practices following reactive interventions leaves #healthcare facilities vulnerable to #Ebola virus transmission

 

Abstract

We assessed impact and durability of an infection prevention and control (IPC) bundle intervention during the Kivu/Ituri Ebolavirus outbreak (2018-2020). IPC scores increased initially, then declined 6 months post-intervention (median 19/36, 30/36, and 28/36, p<0.0001). Without sustained IPC practices, health facilities remain vulnerable to nosocomial transmission in future Ebolavirus outbreaks.

Source: 

Link: https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciag192/8526630

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Incidence of #healthcare-associated #infections in long-term #care #facilities in nine #European countries: a 12-month, prospective, longitudinal cohort study

Summary

Background

The number of older people in need of long-term care is increasing, and health-care-associated infections (HAIs) are a major cause of morbidity and mortality for residents of long-term care facilities (LTCFs). This study, organised by the European Centre for Disease Prevention and Control (ECDC), provided data on the incidence of HAIs and related adverse outcomes in LTCFs in European countries, supplementing the available estimates from repeated point prevalence surveys conducted by the ECDC.

Methods

In this longitudinal, prospective cohort study, we analysed all HAIs collected in a convenience sample of residents from 65 LTCFs (including general nursing homes, residential homes, and mixed facilities) in nine EU or European Economic Area (EEA) countries (Belgium, Finland, France, Italy, Lithuania, Luxembourg, the Netherlands, Poland, and Spain) over 12 months. Eligible residents were those expected to stay in the LTCF for at least the entire study period. Data were collected with three questionnaires: an institutional questionnaire, a residents' questionnaire, and an HAI questionnaire. HAIs were defined according to standard ECDC criteria. The primary outcome was HAI incidence. Incidence measures, estimated using generalised estimating equation models to account for sample heterogeneity, were percentages of each type of HAI, numbers of HAIs per 100 LTCF residents (ratio), and numbers of HAIs per 1000 resident-days (incidence rate).

Findings

HAIs were analysed in 3029 residents of LTCFs between Jan 1–May 4, 2022, and Jan 1–May 12, 2023. The mean age of study participants was 80·9 years (SD 14·6), including 960 (31·7%) men and 2069 (68·3%) women. 3763 HAIs were recorded, with at least one HAI identified in 1717 (57%) of 3029 residents. There were 124·2 HAIs (95% CI 118·6–129·9) per 100 residents and 1·8 HAIs (0·9–3·3) per 1000 resident-days. 160 (4·3% [95% CI 3·9–5·4]) HAIs led to hospitalisation, and 154 (4·5% [2·5–4·8]) were associated with death. Respiratory tract infections (RTIs) were the most frequent type of infection (n=1080, 28·9% [95% CI 27·3–30·5]), including pneumonia (n=279, 7·3% [6·4–8·3]) and other lower RTIs (n=394, 10·7% [9·6–11·8]), followed by urinary tract infections (UTIs; n=743, 18·7% [17·2–20·3]). RTIs showed the highest incidence of mortality (n=85, 2·3% [95% CI 1·8–2·8] of all HAIs). Severe cases of COVID-19 (n=72, 1·9% [95% CI 1·5–2·4] of all HAIs) were less frequent than mild or moderate cases (n=615, 16·0% [14·9–17·1] of all HAIs).

Interpretation

This study shows the high incidence of HAIs among LTCF residents in EU or EEA countries, with more than one in two residents experiencing at least one HAI, and with RTIs and UTIs accounting for almost half of all observed HAIs.

Source: Lancet Infectious Diseases, https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(25)00217-8/fulltext?rss=yes#fig1

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Middle East respiratory syndrome #coronavirus {#MERS-CoV} - Kingdom of #Saudi Arabia (#WHO D.O.N., May 12 '25)

Situation at a glance

Between 1 March and 21 April 2025, the Ministry of Health (MoH) of the Kingdom of Saudi Arabia (KSA) reported nine cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection. Two of these cases died. Among the nine cases, a cluster of seven cases were identified in Riyadh, including six health and care workers who acquired the infection from caring for a single infected patient. The cluster was identified through contact tracing and subsequent testing of all contacts, with four of the six health and care workers being asymptomatic and two showing only mild, nonspecific signs. The notification of these cases does not change the overall risk assessment, which remains moderate at both the global and regional levels. These cases show that the virus continues to pose a threat in countries where it is circulating in dromedary camels and spilling over into the human population. WHO recommends implementation of targeted infection prevention and control (IPC) measures to prevent the spread of health-care-associated infections of MERS-CoV and onward human transmission.

Description of the situation

Between 1 March and 21 April 2025, the Ministry of Health (MoH) of the Kingdom of Saudi Arabia (KSA) reported nine cases of MERS-CoV infection. 

The cases were reported from the Hail (1) and Riyadh (8) regions of Saudi Arabia (Figure 1). Of the reported cases, five were male and four were female.

Among these cases, a cluster of seven was identified in Riyadh, including six health and care workers who acquired a nosocomial infection from one single infected patient they had cared for. 

Of the six health and care workers, four remained asymptomatic, while two developed mild, nonspecific symptoms including myalgia, fatigue, nausea and vomiting (...). 

Laboratory confirmation of the cases was performed by real-time polymerase chain reaction (RT-PCR) between 1 March 2025 and 16 April 2025. 

Of the cases, only one had indirect contact with camels and is not a part of the reported cluster. The rest of the patients had no known history of contact with camels or camel products.

Since the first report of MERS-CoV in KSA in 2012, a total 2627 laboratory-confirmed cases of MERS-CoV infection, with 946 associated deaths (Case Fatality Rate or CFR of 36%), have been reported to WHO from 27 countries, across all six WHO regions. 

The majority of cases (2218; 84%), have been reported from KSA, including these newly reported cases (...). Since 2019, no human MERS-CoV infections have been reported from countries outside the Middle East.

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Epidemiology

Middle East respiratory syndrome (MERS) is a respiratory illness caused by a coronavirus (MERS-CoV). The fatality rate among confirmed cases is around 36%, though this may be an overestimate since milder cases often go undetected. The CFR is calculated based solely on laboratory-confirmed infections, which may not reflect the correct mortality rate.

Humans contract MERS-CoV through direct or indirect contact with dromedary camels, the virus’s natural host and zoonotic reservoir. 

Human-to-human transmission occurs via infectious respiratory particles mainly at close distances and also through contact transmission, it has mainly occurred in close-contact situations, particularly in health-care settings. 

Outside these environments, there has been limited documented human-to-human transmission to date. 

MERS can present with no symptoms, mild respiratory issues, or severe illness leading to acute respiratory distress and death. 

Common symptoms include fever, cough, and breathing difficulties, with pneumonia frequently observed, though not always present. 

Some patients also experience gastrointestinal symptoms such as diarrhoea. 

Severe cases may require intensive care, including mechanical ventilation. Those at higher risk of severe outcomes include older adults, individuals with weakened immune systems, and those with chronic conditions like diabetes, kidney disease, cancer, or lung disorders.

The number of MERS-CoV infections reported to WHO has substantially declined since the beginning of the COVID-19 pandemic. 

Initially, this was likely the result of epidemiological surveillance for SARS-CoV-2 being prioritized. 

The similar clinical picture of both diseases may result in reduced testing and detection of MERS-CoV infections. 

However, the Ministry of Health of KSA has been working to improve testing capacities for better detection of MERS-CoV since the easing of the COVID-19 pandemic, with MERS-CoV included into sentinel surveillance testing algorithms since the second quarter of 2023, for samples that test negative for both influenza and SARS-CoV-2. 

In addition, measures taken to reduce SARS-CoV-2 transmission (e.g., IPC measures such as mask-wearing, hand hygiene, physical distancing, improving the ventilation of indoor spaces, respiratory etiquette, stay-at-home orders, reduced mobility) also likely reduced opportunities for onward human-to-human transmission of MERS-CoV. 

Potential cross-protection conferred from infection with or vaccination against SARS-CoV-2 and any reduction in MERS-CoV infection or disease severity and vice versa has been hypothesized but requires further investigation.

No vaccine or specific treatment is currently available, although several MERS-CoV-specific vaccines and therapeutics are in development. Treatment remains supportive, focusing on managing symptoms based on the severity of the illness.

Public health response

The Ministry of Health of KSA implemented the following response measures

-- Infection prevention and control (IPC) measures in healthcare settings:

- Regular training of health and care workers on IPC measures.

- Implementation of stringent IPC measures, including triage protocols, use of personal protective equipment (PPE), and isolation procedures for suspected cases.

- Prompt isolation of cases and quarantine of contacts.

-- Surveillance and testing:

- Rigorous contact tracing and testing of high-risk contacts, including healthcare workers.

- Inclusion of MERS-CoV in sentinel surveillance testing algorithms since 2023.

-- Public health awareness and hygiene practices:

- Public health awareness campaigns to prevent human-to-human transmission.

- Advising people with underlying chronic medical conditions to avoid close contact with animals, particularly dromedaries.

WHO risk assessment

As of 21 April 2025, a total of 2627 laboratory-confirmed cases of MERS-CoV infection have been reported globally to the WHO, with 946 associated deaths. 

The majority of these cases have occurred in countries within the Arabian Peninsula, with 2218 cases (84.4%) and 865 related deaths (CFR 39%) reported from the KSA. 

A notable outbreak outside the Middle East occurred in the Republic of Korea, in May 2015, during which 186 laboratory-confirmed cases (185 in the Republic of Korea and 1 in China) and 38 deaths were reported. However, the index case in that outbreak had a travel history to the Middle East. 

The global case count reflects laboratory-confirmed cases reported to WHO under IHR (2005) or directly by Ministries of Health to date. These numbers may underestimate the true number of cases if some were not reported. The total number of deaths includes those that WHO has been officially informed of, based on follow-up with affected Member States. 

Humans are infected with MERS-CoV from direct or indirect contact with dromedaries who are the natural host and zoonotic source of the MERS-CoV infection. MERS-CoV has demonstrated the ability to be transmitted between humans. 

So far, the observed non-sustained human-to-human transmission has occurred among close contacts and in health care settings. Outside of the healthcare setting there has been limited human-to human transmission.  

The notification of these cases does not change the overall risk assessment. The reported cluster of six secondary cases among health and care workers is the result of rigorous contact tracing and testing performed by KSA, with four of the six cases being asymptomatic and two showing only mild, unspecific signs. 

WHO expects that additional cases of MERS-CoV infection will be reported from the Middle East and/or other countries where MERS-CoV is circulating in dromedaries, and that cases will continue to be exported to other countries by individuals who were exposed to the virus through contact with dromedaries or their products (for example, consumption of raw camel milk), or in a healthcare setting. 

WHO continues to monitor the epidemiological situation and conducts risk assessment based on the latest available information.  

WHO advice

Based on the current situation and available information, WHO reemphasizes the importance of strong surveillance by all Member States for acute respiratory infections, including MERS-CoV where warranted, and to carefully review any unusual patterns. 

Delays in recognizing the early symptoms of MERS-CoV infection, slow triage of suspected cases and delays in implementing IPC measures have been linked with human-to-human transmission of MERS-CoV in health-care settings in past outbreaks. IPC measures are therefore critical to prevent the spread of healthcare-associated infections of MERS-CoV. Health and care workers should always apply standard precautions consistently with all patients, at every interaction in healthcare settings.

Ventilation rates in general patient care rooms should meet or exceed 60 litres per second per patient (or 6 air changes per hour). 

In addition, contact and droplet precautions, which include patient placement in single rooms with dedicated care equipment, and the use of personal protective equipment (PPE) such as clean non-sterile gown, gloves, eye protection and a well-fitting medical mask, should be added to standard precautions when providing care to patients with suspected or confirmed MERS-CoV. 

Airborne precautions should be added when performing aerosol-generating procedures or in settings where aerosol-generating procedures are conducted, including the use of procedure rooms with ventilation rates meeting or exceeding 160 litres per second (or 12 air changes per hour). 

Early identification, case management and prompt isolation of cases, quarantine of contacts, together with appropriate IPC measures in health care settings and public health awareness can prevent human-to-human transmission of MERS-CoV. 

MERS-CoV appears to cause more severe disease in people with underlying chronic medical conditions such as diabetes, renal failure, chronic lung disease, and immunocompromised persons. Therefore, people with these underlying medical conditions should avoid close contact with animals, particularly dromedaries, when visiting farms, markets, or barn areas where the virus may be circulating.

General hygiene measures, such as regular hand washing before and after touching animals and avoiding contact with sick animals, should be adhered to. 

In addition to contact with animals, hygiene practices should be observed when dealing with food items of camels; people should avoid drinking raw camel milk or camel urine or eating meat that has not been properly cooked. 

WHO does not advise special screening at points of entry with regard to this event, nor does it currently recommend the application of any travel or trade restrictions.

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Citable reference: World Health Organization (12 May 2025). Disease Outbreak News; Middle East Respiratory Syndrome coronavirus – Kingdom of Saudi Arabia. Available at: https://www.who.int/emergencies/disease-outbreak-news/item/2025-DON569

Source: World Health Organization, https://www.who.int/emergencies/disease-outbreak-news/item/2025-DON569

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