Influenza outbreak in a correctional facility

Outbreak of COVID-19 and interventions in a large jail - Cook County, IL, United States, 2020

Background

Correctional and detention facilities are disproportionately affected by COVID-19 due to shared space, contact between staff and detained persons, and movement within facilities. On March 18, 2020, Cook County Jail, one of the United States’ largest, identified its first suspected case of COVID-19 in a detained person.

Methods

This analysis includes SARS-CoV-2 cases confirmed by molecular detection among detained persons and Cook County Sheriff's Office staff. We examined occurrence of symptomatic cases in each building and proportions of asymptomatic detained persons testing positive, and timing of interventions including social distancing, mask use, and expanded testing and show outbreak trajectory in the jail compared to case counts in Chicago.

Results

During March 1-April 30, 907 symptomatic and asymptomatic cases of SARS-CoV-2 infection were detected among detained persons (n = 628) and staff (n = 279). Among asymptomatic detained persons in quarantine, 23.6% tested positive. Programmatic activity and visitation stopped March 9, cells were converted into single occupancy beginning March 26, and universal masking was implemented for staff (April 2) and detained persons (April 13). Cases at the jail declined while cases in Chicago increased.

Discussion/Conclusions

Aggressive intervention strategies coupled with widespread diagnostic testing of detained and staff populations can limit introduction and mitigate transmission of SARS-CoV-2 infection in correctional and detention facilities.

Managing outbreaks of highly contagious diseases in prisons: a systematic review

BACKGROUND

There are reports of outbreaks of COVID-19 in prisons in many countries. Responses to date have been highly variable and it is not clear whether public health guidance has been informed by the best available evidence. We conducted a systematic review to synthesise the evidence on outbreaks of highly contagious diseases in prison.

METHODS

We searched seven electronic databases for peer-reviewed articles and official reports published between 1 January 2000 and 28 July 2020. We included quantitative primary research that reported an outbreak of a given contagious disease in a correctional facility and examined the effects of interventions. We excluded studies that did not provide detail on interventions. We synthesised common themes using the Synthesis Without Meta-analysis (SWiM) guideline, identified gaps in the literature and critically appraised the effectiveness of various containment approaches.

RESULTS

We identified 28 relevant studies. Investigations were all based in high-income countries and documented outbreaks of tuberculosis, influenza (types A and B), varicella, measles, mumps, adenovirus and COVID-19. Several themes were common to these reports, including the public health implications of infectious disease outbreaks in prison, and the role of interagency collaboration, health communication, screening for contagious diseases, restriction, isolation and quarantine, contact tracing, immunisation programmes, epidemiological surveillance and prison-specific guidelines in addressing any outbreaks.

DISCUSSION

Prisons are high-risk settings for the transmission of contagious diseases and there are considerable challenges in managing outbreaks in them. A public health approach to managing COVID-19 in prisons is required.

PROSPERO REGISTRATION NUMBER

CRD42020178827.

Prevalence and factors influencing the distribution of influenza viruses in Kenya: Seven-year hospital-based surveillance of influenza-like illness (2007-2013)

Background

Influenza viruses remain a global threat with the potential to trigger outbreaks and pandemics. Globally, seasonal influenza viruses’ mortality range from 291 243–645 832 annually, of which 17% occurs in Sub-Saharan Africa. We sought to estimate the overall prevalence of influenza infections in Kenya, identifying factors influencing the distribution of these infections, and describe trends in occurrence from 2007 to 2013.

Methods

Surveillance was conducted at eight district hospital sites countrywide. Participants who met the case definition for influenza-like illness were enrolled in the surveillance program. The nasopharyngeal specimens were collected from all participants. We tested all specimens for influenza viruses with quantitative reverse transcriptase real-time polymerase chain reaction (RT-qPCR) assay. Bivariate and multivariate log-binomial regression was performed with a statistically significant level of p<0.005. An administrative map of Kenya was used to locate the geographical distribution of surveillance sites in counties. We visualized the monthly trend of influenza viruses with a graph and chart using exponential smoothing at a damping factor of 0.5 over the study period (2007–2013).

Results

A total of 17446 participants enrolled in the program. The overall prevalence of influenza viruses was 19% (n = 3230), of which 76% (n = 2449) were type A, 21% (n = 669) type B and 3% (n = 112) A/ B coinfection. Of those with type A, 59% (n = 1451) were not subtyped. Seasonal influenza A/H3N2 was found in 48% (n = 475), influenza A/H1N1/pdm 2009 in 43% (n = 434), and seasonal influenza A/ H1N1 in 9% (n = 88) participants. Both genders were represented, whereas a large proportion of participants 55% were ≤1year age. Influenza prevalence was high, 2 times more in other age categories compared to ≤1year age. Category of occupation other than children and school attendees had a high prevalence of influenza virus (p< <0.001). The monthly trends of influenza viruses’ positivity showed no seasonal pattern. Influenza types A and B co-circulated throughout the annual calendar during seven years of the surveillance.

Conclusions

Influenza viruses circulate year-round and occur among children as well as the adult population in Kenya. Occupational and school-based settings showed a higher prevalence of influenza viruses. There were no regular seasonal patterns for influenza viruses.

[Mental health care in French correctional facilities during the Covid-19 pandemic]

OBJECTIVE

The impact of the Covid-19 pandemic on the 11 million people currently incarcerated worldwide is the subject of many concerns. Prisons and jails are filled with people suffering from many preexisting medical conditions increasing the risk of complications. Detainees' access to medical services is already limited and overcrowding poses a threat of massive contagion. Beyond the health impact of the crisis, the tightening of prison conditions worries. On March 16, 2020, in France, the lockdown measures have been accompanied by specific provisions for prisons: all facilities have suspended visitations, group activities and external interventions. Over 10,000 prisoners have been released to reduce the prison population and the risk of virus propagation. These adjustments had major consequences on the healthcare system in French prisons. The objectives of this article are to describe the reorganization of the three levels of psychiatric care for inmates in France in the context of Covid-19 pandemic and to have a look at the impact of lockdown measures and early releases on mental health of prisoners.

METHODS

This work is based on a survey conducted in April 2020 in France among psychiatric healthcare providers working in 42 ambulatory units for inmates and in the 9 full-time inpatient psychiatric wards exclusively for inmates called "UHSAs" (which stands for "unités hospitalières spécialement aménagées", and can be translated as "specially equipped hospital units"). A review of the international literature on mental healthcare system for inmates during the Covid-19 epidemic has also been performed.

RESULTS

The Covid-19 epidemic has been rather contained during the period of confinement in French prisons but the impact of confinement measures on the prison population is significant. The three levels of psychiatric care for inmates have implemented specific measures to ensure continuity of care, to support detainees during Coronavirus lockdown and to prevent an infection's spread. Among the most important are: limitation of medical consultations to serious and urgent cases, creation of "Covid units", cancellation of voluntary psychiatric hospitalizations, reinforcement of preventive hygiene measures and reshuffling of medical staff. Prolonged confinement has consequences on mental health of detainees. Currently, mental health workers are facing multiple clinical situations such as forced drug and substance withdrawal (linked to difficulties in supplying psychoactive substances), symptoms of anxiety (due to concerns for their own and their relatives' well-being) and decompensation among patients with severe psychiatric conditions. Early releases from prison may also raise some issues. People recently released from prison are identified as at high risk of death by suicide and drug overdose. The lack of time to provide the necessary link between health services within prisons and health structures outside could have serious consequences, emphasizing the well-known "revolving prison doors" effect.

DISCUSSION

The current lockdown measures applied in French jails and prisons point out the disparities between psychiatric care for inmates and psychiatric care for general population. Giving the high vulnerability of prison population, public health authorities should pay more attention to health care in prisons.

A systematic scoping review of environmental health conditions in penal institutions

Adequate environmental health conditions in penal institutions are necessary to protect and promote the health of prisoners and prison workers. We conducted a scoping systematic review to: describe the environmental health conditions in penal institutions and the associated exposures and health outcomes; identify effective approaches to prevent environmental health concerns; and identify evidence gaps on environmental health in penal institution populations. PubMed, Web of Science, EBSCOhost, Scopus, and ProQuest were searched. Peer-reviewed studies that reported original data and on environmental health conditions and/or exposures in penal institutions were included. Seventy-three studies met these criteria. The most common risk factor identified was contaminated food and/or beverages prepared or handled in the institution's kitchen. Overcrowding, inadequate ventilation, and a lack of, or sharing of, soap and other hygiene products increased the risk of adverse health outcomes. Common responses included isolating infectious patients, educating prisoners and prison staff on improved sanitation and hygiene practices, improving ventilation, and disinfecting contaminated surfaces and/or water sources. Inadequate environmental health conditions in penal institutions are common, and adversely impact the health of prisoners and prison staff, yet are preventable. Few studies have been conducted in low- and middle-income countries, biasing our results. The development and implementation of national guidelines for essential environmental health in prisons, monitoring of conditions, and greater accountability of facility managers are needed to secure the health, rights, and well-being of prisoners.

Influenza outbreak in a Canadian correctional facility

Correctional facilities face increased risk of communicable disease transmission and outbreaks. We describe the progression of an influenza outbreak in a Canadian remand facility and suggest strategies for preventing, identifying and responding to outbreaks in this setting. In total, six inmates had laboratory-confirmed influenza resulting in 144 exposed contacts. Control measures included enhanced isolation precautions, restricting admissions to affected living units, targeted vaccination and antiviral prophylaxis. This report highlights the importance of setting specific outbreak guidelines in addressing population and environmental challenges, as well as implementation of effective infection prevention and control (IPAC) and public health measures when managing influenza and other communicable disease outbreaks.

Vaccinations in prisons: A shot in the arm for community health

From the first day of imprisonment, prisoners are exposed to and expose other prisoners to various communicable diseases, many of which are vaccine-preventable. The risk of acquiring these diseases during the prison sentence exceeds that of the general population. This excess risk may be explained by various causes; some due to the structural and logistical problems of prisons and others to habitual or acquired behaviors during imprisonment. Prison is, for many inmates, an opportunity to access health care, and is therefore an ideal opportunity to update adult vaccination schedules. The traditional idea that prisons are intended to ensure public safety should be complemented by the contribution they can make in improving community health, providing a more comprehensive vision of safety that includes public health.

Influenza B outbreak on a cruise ship off the São Paulo Coast, Brazil

BACKGROUND

In February 2012, crew and passengers of a cruise ship sailing off the coast of São Paulo, Brazil, were hospitalized for acute respiratory illness (ARI). A field investigation was performed to identify the disease involved and factors associated.

METHODS

Information on passengers and crew with ARI was obtained from the medical records of hospitalized individuals. Active case finding was performed onboard the ship. ARI was defined as the presence of one nonspecific symptom (fever, chills, myalgia, arthralgia, headache, or malaise) and one respiratory symptom (cough, nasal congestion, sore throat, or dyspnea). A case-control study was conducted among the crew. The cases were crew members with symptoms of influenza-like illness (ILI) (fever and one of the following symptoms: cough, sore throat, and dyspnea) in February 2012. The controls were asymptomatic crew members.

RESULTS

The study identified 104 ARI cases: 54 (51.9%) crew members and 50 (49.1%) passengers. Among 11 ARI hospitalized cases, 6 had influenza B virus isolated in nasopharyngeal swab. One mortality among these patients was caused by postinfluenza Staphylococcus aureus pneumonia. The crew members housed in the two lower decks and those belonging to the 18- to 32-year-old age group were more likely to develop ILI [odds ratio (OR) = 2.39, 95% confidence interval (CI) 1.09-5.25 and OR = 3.72, CI 1.25-11.16, respectively].

CONCLUSIONS

In February 2012, an influenza B outbreak occurred onboard a cruise ship. Among crew members, ILI was associated with lower cabin location and younger age group. This was the first influenza outbreak detected by Brazilian public health authorities in a vessel cruising in South American waters.

Routes of influenza transmission

Remarkably little is known definitively about the modes of influenza transmission. Thus, important health policy and infection control issues remain unresolved. These shortcomings have been exposed in national and international pandemic preparedness activities over recent years. Indeed, WHO, CDC, ECDC and the U.S. Institute of Medicine have prioritised understanding the modes of influenza transmission as a critical need for pandemic planning. Studying influenza transmission is difficult; seasonality, unpredictable attack rates, role of environmental parameters such as temperature and humidity, numbers of participants required and confounding variables all present considerable obstacles to the execution of definitive studies. A range of investigations performed to date have failed to provide definitive answers and key questions remain. Reasons for this include the fact that many studies have not sought to investigate routes of transmission as a primary objective (instead, they have evaluated specific interventions) and that fieldwork in natural settings, specifically assessing the dynamics and determinants of transmission between humans, has been limited. The available evidence suggests that all routes of transmission (droplet, aerosol and contact) have a role to play; their relative significance will depend on the set of circumstances acting at a given time. Dictating the process are factors related to the virus itself, the host and the environment.

National surveillance for influenza and influenza-like illness in Vietnam, 2006-2010

Influenza virus infections result in considerable morbidity and mortality both in the temperate and tropical world. Influenza surveillance over multiple years is important to determine the impact and epidemiology of influenza and to develop a national vaccine policy, especially in countries developing influenza vaccine manufacturing capacity, such as Vietnam. We conducted surveillance of influenza and influenza-like illness in Vietnam through the National Influenza Surveillance System during 2006-2010. At 15 sentinel sites, the first two patients presenting each weekday with influenza-like illness (ILI), defined as fever and cough and/or sore throat with illness onset within 3 days, were enrolled and throat specimens were collected and tested for influenza virus type and influenza A subtype by RT-PCR. De-identified demographic and provider reported subsequent hospitalization information was collected on each patient. Each site also collected information on the total number of patients with influenza-like illness evaluated per week. Of 29,804 enrolled patients presenting with influenza-like illness, 6516 (22%) were influenza positive. Of enrolled patients, 2737 (9.3%) were reported as subsequently hospitalized; of the 2737, 527 (19%) were influenza positive. Across all age groups with ILI, school-aged children had the highest percent of influenza infection (29%) and the highest percent of subsequent hospitalizations associated with influenza infection (28%). Influenza viruses co-circulated throughout most years in Vietnam during 2006-2010 and often reached peak levels multiple times during a year, when >20% of tests were influenza positive. Influenza is an important cause of all influenza-like illness and provider reported subsequent hospitalization among outpatients in Vietnam, especially among school-aged children. These findings may have important implications for influenza vaccine policy in Vietnam.

An analysis of influenza outbreaks in institutions and enclosed societies

This paper considers the reported attack ratio arising from outbreaks of influenza in enclosed societies. These societies are isolated from the wider community and have greater opportunities for contact between members which would aid the spread of disease. While the particular kind of society (prison, care home, school, barracks, etc.) was not a significant factor in an adjusted model of attack ratio, a person's occupation within the society was. In particular, children and military personnel suffer a greater attack ratio than other occupational types (staff, prisoners, etc.). There was no temporal trend in final attack ratio nor, with the exception of 1918, do pandemic years show abnormal attack ratios. We also observed that as community size increases, the attack ratio undergoes steep nonlinear decline. This statistical analysis draws attention to how the organization of such societies, their size and the occupations of individuals within them affect the final attack ratio.

A mouse model for the study of contact-dependent transmission of influenza A virus and the factors that govern transmissibility

Influenza A virus transmission by direct contact is not well characterized. Here, we describe a mouse model for investigation of factors regulating contact-dependent transmission. Strains within the H3N2 but not H1N1 subtype of influenza virus were transmissible, and reverse-engineered viruses representing hybrids of these subtypes showed that the viral hemagglutinin is a determinant of the transmissible phenotype. Transmission to contact mice occurred within the first 6 to 54 h after cohousing with directly infected index mice, and the proportion of contacts infected within this period was reduced if the index mice had been preinfected with a heterologous subtype virus. A threshold level of virus present in the saliva of the index mice was identified, above which the likelihood of transmission was greatly increased. There was no correlation with transmission and viral loads in the nose or lung. This model could be useful for preclinical evaluation of antiviral and vaccine efficacy in combating contact-dependent transmission of influenza.

Behaviour and control of influenza in institutions and small societies

A literature review was undertaken to assess the impact of influenza in enclosed societies. The literature spanned 120 years and included both readily accessible material from online keyword searches, as well as more obscure paper documents found through in-depth library research. Enclosed societies have been predominantly found in some type of institution through this period although noticeable similarities exist in communities isolated by distance and geography. We observe that no matter how isolated a community is, it is not necessarily insulated from infection by influenza and that even where there are no complicating factors, such as the age distribution or the presence of individuals with greater susceptibility in the enclosed population, their organization tends to increase influenza transmission and the risk of secondary infection. The collected accounts demonstrate important features of outbreaks in such societies and the necessity of considering them in pandemic planning: in particular, rapid intervention is essential for the control of influenza spread in such circumstances. Recent experience has shown that administration of modern antiviral drugs, such as neuraminidase inhibitors are effective at moderating outbreaks of influenza, but only in combination with other methods of control. In more remote communities where such drugs are not, or less, readily available, and medical care is limited, such outbreaks can still pose particular difficulties. In all cases delay in correct diagnosis, detection of an outbreak or the implementation of control measures can result in the majority of the enclosed population succumbing to the disease.

Spatial dynamics of airborne infectious diseases

Disease outbreaks, such as those of Severe Acute Respiratory Syndrome in 2003 and the 2009 pandemic A(H1N1) influenza, have highlighted the potential for airborne transmission in indoor environments. Respirable pathogen-carrying droplets provide a vector for the spatial spread of infection with droplet transport determined by diffusive and convective processes. An epidemiological model describing the spatial dynamics of disease transmission is presented. The effects of an ambient airflow, as an infection control, are incorporated leading to a delay equation, with droplet density dependent on the infectious density at a previous time. It is found that small droplets (∼0.4μm) generate a negligible infectious force due to the small viral load and the associated duration they require to transmit infection. In contrast, larger droplets (∼4μm) can lead to an infectious wave propagating through a fully susceptible population or a secondary infection outbreak for a localized susceptible population. Droplet diffusion is found to be an inefficient mode of droplet transport leading to minimal spatial spread of infection. A threshold air velocity is derived, above which disease transmission is impaired even when the basic reproduction number R(0) exceeds unity.

Molecular characteristics of outbreaks of nosocomial infection with influenza A/H3N2 virus variants

OBJECTIVE

To describe outbreaks of nosocomial influenza infection with molecular methods and to elucidate the viral linkages among outbreak case patients including both inpatients and healthcare workers (HCWs).

SETTING

A 180-bed acute and long-term care hospital in Japan.

METHODS

Retrospective observational study of nosocomial outbreaks of infection with influenza A/H3N2. Together with information about onset dates and vaccination history, we obtained nasopharyngeal swab samples from individuals with cases of influenza or influenza-like illness (ILI). The hemagglutinin genes of the recovered viruses were sequenced and compared, along with those of community-circulating strains, for similarity by phylogenetic tree analysis.

RESULTS

The outbreaks occurred from February 26 through April 3, 2007, during the 2006-2007 epidemic season, and they involved 11 patients and 13 HCWs. The 2 outbreaks involved 2 different genotypes of influenza A/H3N2 viruses. These virus variants were closely related to the influenza strains that were circulating in the community during the same epidemic season.

CONCLUSION

This study showed the dissemination of highly homologous influenza virus variants among inpatients and HCWs within a short period, as a result of nosocomial transmission. These strains were also similar to influenza strains that were circulating in the community.

Face masks to prevent transmission of influenza virus: a systematic review

Influenza viruses circulate around the world every year. From time to time new strains emerge and cause global pandemics. Many national and international health agencies recommended the use of face masks during the 2009 influenza A (H1N1) pandemic. We reviewed the English-language literature on this subject to inform public health preparedness. There is some evidence to support the wearing of masks or respirators during illness to protect others, and public health emphasis on mask wearing during illness may help to reduce influenza virus transmission. There are fewer data to support the use of masks or respirators to prevent becoming infected. Further studies in controlled settings and studies of natural infections in healthcare and community settings are required to better define the effectiveness of face masks and respirators in preventing influenza virus transmission.

Transmission of influenza A in human beings

Planning for the next influenza pandemic is occurring at many levels throughout the world, spurred on by the recent spread of H5N1 avian influenza in Asia, Europe, and Africa. Central to these planning efforts in the health-care sector are strategies to minimise the transmission of influenza to health-care workers and patients. The infection control precautions necessary to prevent airborne, droplet, and contact transmission are quite different and will need to be decided on and planned before a pandemic occurs. Despite vast clinical experience in human beings, there continues to be much debate about how influenza is transmitted. We have done a systematic review of the English language experimental and epidemiological literature on this subject to better inform infection control planning efforts. We have found that the existing data are limited with respect to the identification of specific modes of transmission in the natural setting. However, we are able to conclude that transmission occurs at close range rather than over long distances, suggesting that airborne transmission, as traditionally defined, is unlikely to be of significance in most clinical settings. Further research is required to better define conditions under which the influenza virus may transmit via the airborne route.

Prevention of infectious disease transmission in correctional settings: a review

OBJECTIVES

To review studies defining risk factors for infectious disease transmission in correctional settings, to determine target objectives, and to assemble recommendations for health promotion in prisons and jails.

METHODS

Electronic databases were searched, using a specific search strategy, from 1993 to 2003.

RESULTS

The principal risk factors in correctional facilities are proximity, high-risk sexual behaviour and injection drug use. Based on the type of disease transmissions and epidemics reported in the literature, four diseases were targeted for which preventive measures should be implemented: tuberculosis, human immunodeficiency virus, hepatitis and sexually transmitted diseases. Knowledge of risk factors helps define effective preventive measures along five main themes of action: information and education, screening, limiting harm from risk behaviour by distributing condoms and exchanging syringes, treatment and vaccinations.

CONCLUSIONS

The effectiveness and feasibility of each of these actions have to be assessed in relation to the specificities of the correctional setting.

Selected nonvaccine interventions to prevent infectious acute respiratory disease

INTRODUCTION

Infectious acute respiratory disease (ARD) is a significant cause of worldwide morbidity, disproportionately affecting individuals living in crowded conditions, such as found at military training centers, school dormitories, and correctional facilities. Vaccines have been used to protect against ARD; however, these are not always available or effective.

METHODS

The medical literature (1963-2004) on preventive nonvaccine ARD interventions (NOVARDIs) for infectious diseases, which addressed personal measures, administrative controls, and engineering controls, was studied during 2000 to 2004. Population-based studies in community settings (non-health care) were reviewed in detail to evaluate the effectiveness of NOVARDIs. Budgetary and logistic factors as well as acceptance were considered in formulating recommendations for implementation of NOVARDIs in military training centers.

RESULTS

Thirty-eight population-based studies contained in 35 publications were examined. Three studies contained information on multiple NOVARDIs. Nine studies supported the use of personal measures relating to hand hygiene. Ten studies supported administrative controls such as cohorting military training units to reduce contact between units (4 studies), providing adequate personal space to reduce crowding (5), and cloth barriers between beds (1); and 14 studies supported the use of engineering controls such as increased indoor air dilution and ventilation (2), dust suppression (4), and air sterilization (8).

CONCLUSIONS

Promoting hand hygiene and reducing crowding through the provision of adequate living space and cohorting of training units may offer benefits in respiratory disease control. These interventions, along with UV lights and air dilution/ventilation, deserve further evaluation in controlled studies to assess their efficacy. NOVARDIs could benefit military and other populations living in close contact.

Influenza control in Australian prison settings: Cost ‐ benefit analysis of major strategies

Repeated influenza outbreaks are surprisingly rare in prison settings worldwide, a factor that has made it superfluous, to date, to develop contingency plans for responding to prison‐based influenza epidemics. However, the influenza outbreak that occurred in an Australian prison in 2000 has highlighted the appropriateness of developing an outbreak plan, not least because of the security implications of a widespread prison influenza epidemic. Using reported attack rates and morbidity profiles of the 2000 Australian prison influenza outbreak to develop scenarios, the authors estimated the cost ‐ benefit of mass vaccination and antiviral chemotherapy approaches for the control of hypothetical widespread influenza outbreaks in New South Wales prisons, occurring at an average frequency of once every 10 years. It was concluded that, from the perspectives of maintaining prison security as well as health care services’ provision to prisoners, early antiviral chemotherapy for symptomatic individuals will have more favourable cost ‐ benefit ratios than a mass vaccination approach for controlling prison‐based influenza outbreaks that occur in line with this model.

New point of care test is highly specific but less sensitive for influenza virus A and B in children and adults

The importance of rapid diagnosis of influenza has increased with the availability of neuraminidase inhibitors, which need to be commenced within 48 hr of symptom onset. Furthermore, the recent development of influenza-like clinical syndromes with novel aetiologies (severe acute respiratory syndrome, SARS) has increased the need for rapid and accurate near-patient diagnosis. A new, modified point of care (POC) diagnostic test (ZstatFlu) was assessed on 469 nasopharyngeal aspirates (NPAs) and 260 nose/throat swabs (TS) taken from children and adults. The test was specific (77-98%) for all specimen types for influenza virus A and B, depending upon incubation conditions. However, it was less sensitive, detecting 65-77% of specimens confirmed as positive on culture, direct immunofluorescence or PCR testing. A positive test is useful, for both directing initiation of therapy in the clinician's office, and making a positive diagnosis of influenza in patients with influenza-like clinical syndromes.