High Case Fatality Ratio Research Articles

First line therapy: have we made any improvement?

The incidence of epithelial ovarian cancer varies throughout the world (Fig. 1), with higher frequencies in Europe, North America, and Australia, and lower frequencies in much of Asia, Central America, South America, and North Africa [1]. The epidemiologic factors responsible for this variability remain to be defined. However, regardless of where it occurs, ovarian cancer is associated with the highest case-fatality ratio among the gynaecologic cancers, reflecting a propensity for early peritoneal dissemination, and advanced-stage disease at clinical diagnosis. Approximately 80% of advanced-stage tumours demonstrate high-grade serous histology, and these tumours can arise from the distal (fimbriated) fallopian tube, peritoneal cavity, or surface epithelium of the ovary. While high-grade serous tumours can also arise from the endometrium, these tumours have a somewhat different biology, and are generally managed as endometrial cancer, and are not included in clinical trials of ovarian cancer. As such, most of our current

O6-4.3 Poliomyelitis epidemic in Pointe-Noire, October–December 2010: troubled times ahead for global polio eradication?

IntroductionOn 4 November 2010, the Ministry of Health of the Republic of Congo declared a poliomyelitis outbreak in Pointe-Noire, the eastern economic capital. We conducted an outbreak investigation to describe...

Concurrent Influenza and Shigellosis Outbreaks, Papua New Guinea, 2009

Concurrent Influenza and Shigellosis Outbreaks, Papua New Guinea, 2009

Rotavirus Disease in Guinea‐Bissau, West Africa: A Review of Longitudinal Community and Hospital Studies

Rotavirus is one of the most common causes of childhood diarrheal disease and deaths in sub-Saharan Africa. This article reviews community- and hospital-based surveillance of rotavirus disease in Bissau, Guinea-Bissau, West Africa. Here, rotavirus infections exhibit a seasonal pattern, with annual epidemics occurring during the relatively dry and cooler months, from January to April, and few cases registered from May to December. Most children (74%) experience their first infection before the age of 2 years, and rotavirus has been identified as the most pathogenic of all diarrheal agents during 2 large prospective studies involving several hundred children <5 years of age. In the hospital setting, rotavirus accounts for a high case-fatality ratio (8%) and a high rate of nosocomial transmission; during the rotavirus season, 23% of all children admitted for nonrotavirus diarrheal disease acquired rotavirus infection during hospitalization (>48 h after admission).

Increased incidence of meningococcal disease in HIV-infected individuals associated with higher case-fatality ratios in South Africa

We aimed to compare the incidence of meningococcal disease amongst HIV-infected and uninfected individuals and to evaluate whether HIV is a risk factor for mortality and bacteremia amongst patients with meningococcal disease. Cohort surveillance study. We conducted laboratory-based surveillance for meningococcal disease in Gauteng Province, South Africa. HIV status and outcome data were obtained at sentinel sites. Incidence in HIV-infected and uninfected persons was calculated assuming a similar age-specific HIV prevalence in tested and untested individuals. Risk factors for death and bacteremia (as compared with meningitis) were evaluated using multivariable logistic regression. From 2003 to 2007, 1336 meningococcal cases were reported. Of 504 patients at sentinel sites with known outcome, 308 (61%) had HIV serostatus data. HIV prevalence amongst cases of meningococcal disease was higher than the population HIV prevalence in all age groups. The incidence of meningococcal disease in HIV-infected individuals was elevated in all age groups with an age-adjusted relative risk of 11.3 [95% confidence interval (CI) 8.9-14.3, P < 0.001]. The case-fatality ratio (CFR) was 20% (27/138) amongst HIV-infected and 11% (18/170) amongst HIV-uninfected individuals [odds ratio (OR) 2.1, 95% CI 1.1-3.9]. On multivariable analysis, CFR was greater amongst patients with bacteremia (35%, 29/82) compared with meningitis (7%, 16/226) (OR 7.8, 95% CI 3.4-17.7). HIV infection was associated with increased odds of bacteremia (OR 2.7, 95% CI 1.5-5.0). HIV-infected individuals may be at increased risk of meningococcal disease. The increased CFR in HIV-infected patients may be explained by their increased odds of bacteremia compared to meningitis.

The influenza challenge

The presentation aims at introducing the various challenges faced at global level during the first pandemic of the 21st century. On 25 April 2009, Mexico, under the International Health Regulations (2005) (IHR (2005)), notified the World Health Organization (WHO) about an outbreak of influenza-like illness. The responsible virus was identified a few days later by a WHO Collaborating Centre for Reference and Research on Influenza and a reference laboratory in Canada. This was the first reported event related to Influenza A (H1N1). In less than nine weeks, the pandemic virus spread in the six WHO regions. On 11 June 2009, WHO announced a pandemic phase 6. Because of the threat posed by the re emergence of A(H5N1)virus in 2003 in Asia, most of the influenza experts and modellers were predicting that the next pandemic would start in Asia with similar characteristic as the H5N1 disease currently observed with a high case fatality ratio. One of the lessons learned is that predictions are very difficult when related to influenza viruses due their unpredictable evolution and the complexity of factors leading to pandemic. The pandemic (H1N1) 09 is challenging in many aspects: firstly, the uncertainty about the evolution of the virus makes mid term preparedness and planning difficult. Secondly, the weakness of some surveillance system does not allow an easy monitoring of the disease and its spread. The oseltamivir resistance monitoring has also been difficult in some parts of the world. Thirdly, the modern communications means enable rumours to spread faster than ever. Public health authorities have to include risk communication in their strategy to respond to the outbreak. The nature of this pandemic with moderate severity and very rapid spread imposed to revise national pandemic preparedness plans during the course of the event. The public and the media often misunderstood the rational for the modification. The international community has responded quite well to the pandemic threat. In particular, countries have been especially collaborative regarding the exchange of information and the global access to supplies such as vaccine and antiviral drugs.

InvasiveHaemophilus influenzaeDisease, Europe, 1996–2006

An international collaboration was established in 1996 to monitor the impact of routine Haemophilus influenzae type b (Hib) vaccination on invasive H. influenzae disease; 14 countries routinely serotype all clinical isolates. Of the 10,081 invasive H. influenzae infections reported during 1996-2006, 4,466 (44%, incidence 0.28 infections/100,000 population) were due to noncapsulated H. influenzae (ncHi); 2,836 (28%, 0.15/100,000), to Hib; and 690 (7%, 0.036/100,000), to non-b encapsulated H. influenzae. Invasive ncHi infections occurred in older persons more often than Hib (median age 58 years vs. 5 years, p<0.0001) and were associated with higher case-fatality ratios (12% vs. 4%, p<0.0001), particularly in infants (17% vs. 3%, p<0.0001). Among non-b encapsulated H. influenzae, types f (72%) and e (21%) were responsible for almost all cases; the overall case-fatality rate was 9%. Thus, the incidence of invasive non-type b H. influenzae is now higher than that of Hib and is associated with higher case fatality.

Clostridium difficile Infection in the Intensive Care Unit

Clostridium difficile infection (CDI) is an increasing nosocomial problem in North America and Western Europe, where outbreaks caused by a more virulent, toxin-hyperproducing strain have been recently reported. Clostridium difficile infection is now characterized by a higher incidence, more frequent relapses, and a higher case-fatality ratio. As a consequence, fulminant cases requiring admission to the intensive care unit (ICU) are much more common than previously. In recent years, metronidazole has appeared to lose some of its effectiveness in CDI management and vancomycin is now recognized as the first-line treatment of severe cases. Rapid diagnosis and institution of infection control measures are critical components of CDI management. The current review focuses on recent changes in the epidemiology, diagnostic methods, and treatment of CDI, with special emphasis on complicated cases managed in the ICU.

Strategies for mitigating an influenza pandemic with pre-pandemic H5N1 vaccines

The recent worldwide spread of the swine-origin H1N1 2009 influenza outbreak has resulted in its designation as a pandemic by the World Health Organization. While it appears to result in mild symptoms, concern still exists that a more severe influenza pandemic with a high case fatality ratio might arise by reassortment or mutation of the currently circulating avian influenza (H5N1) virus. Given that recently developed candidate pre-pandemic H5N1 vaccines have shown potential for cross-strain protection, we investigated alternative vaccination strategies that exploit such vaccines using an agent-based simulation model of an actual community of approximately 30 000 people in a developed country. Assuming that a two-dose vaccination regimen would be required, we examined three vaccination strategies: pre-emptive, with vaccination applied prior to emergence of human-transmissible H5N1 influenza; reactive, where vaccination was initiated immediately after the first cases in the community were diagnosed; and a 'split' strategy where the first dose was administered pre-emptively during the pre-pandemic phase, with the second dose administered reactively. We showed that by effectively moving the delay between first and second doses into the pre-pandemic period, the split vaccination strategy achieved a substantially better attack rate reduction than the reactive strategy. Our results for an influenza strain with a reproduction number of 1.5 suggest reactive vaccination strategies that may be applicable to the current H1N1 2009 pandemic.

Hantavirus pulmonary syndrome in Brasilia periphery: a diagnostic challenge

Hantavirus pulmonary syndrome (HPS) is an emerging rodent-borne disease in the American continent, characterized by acute respiratory distress and a high case-fatality ratio. The present work describes a case of HPS, with favorable outcome, whose initial features were mistaken for leptospirosis or other less severe acute infections. The case of a 32-year-old male with an uneventful course of HPS is reported. He was inadvertently infected at work by exposure to a rodent-contaminated environment in Brasília, Federal District vicinity, during May 2008. Fever, headache and myalgia after exposure to a rodent-contaminated environment raised clinical suspicion. Non-cardiac pulmonary edema, hydrothorax, neutrophilia with band forms 26%, high hematocrit, thrombocytopenia, and elevated liver enzymes were observed. Leptospirosis and dengue were the main differential diagnoses because both pathogens are endemic in the area. Hantavirus IgM antibody-capture ELISA was positive, while tests for dengue, leptospirosis and yellow fever were negative. The prognosis for HPS is ominous and misdiagnoses may increase mortality. Better chances of survival depend on prompt intensive care support. Reports of moderate or less typical cases can raise the suspicion index among primary care and hospital-based physicians about this uncommon but severe condition that often affects previously healthy young individuals from developing countries, and subjects who interact with rodent-infested environments in North America. High awareness of HPS allowed successful management of the patient, even before establishing the diagnosis, by serological tests at the reference laboratory of the Ministry of Health. Clinical suspicion favored warning local health authorities about a new case of HPS.

Case fatality of SARS in mainland China and associated risk factors

Summary Objective To analyse the case fatality ratio (CFR) and its risk factors for severe acute respiratory syndrome (SARS) in mainland China by using a comprehensive dataset of all probable cases. Methods The data of all probable SARS cases were derived from the Infectious Disease Reporting System of the Center of Diseases Control and Hospital Information Systems, during the 2003 epidemic in mainland China. The definition of probable SARS case was consistent with the definition for clinically confirmed SARS issued by the Ministry of Health of the People’s Republic of China. We performed univariate and multivariate logistic regression analysis to determine the association of CFR with age, sex, residence location, occupation, the period of the epidemic and the duration from symptom onset to admission into hospital. Results The overall CFR was 6.4% among 5327 probable SARS cases in mainland China. Old age, being a patient during the early period of a local outbreak, and being from Tianjin led to a relatively higher CFR than young age, late stage of a local outbreak and cases from Beijing. Guangdong Province resulted in an even lower CFR compared with Beijing. Conclusions Because of their deteriorated health status and apparent complications, SARS patients aged >60 years had a much higher risk of dying than younger patients. At the early stage of local outbreaks, lack of experience in patient care and perhaps treatment also led to a relatively higher CFR. The Tianjin SARS outbreak happened mainly within a hospital, leading to a high impact of co‐morbidity. The relatively young age of the cases partly explains the low CFR in mainland China compared with other countries and areas affected by SARS.

Measles deaths in Nepal: estimating the national case-fatality ratio

To estimate the case-fatality ratio (CFR) for measles in Nepal, determine the role of risk factors, such as political instability, for measles mortality, and compare the use of a nationally representative sample of outbreaks versus routine surveillance or a localized study to establish the national CFR (nCFR). This was a retrospective study of measles cases and deaths in Nepal. Through two-stage random sampling, we selected 37 districts with selection probability proportional to the number of districts in each region, and then randomly selected within each district one outbreak among all those that had occurred between 1 March and 1 September 2004. Cases were identified by interviewing a member of each and every household and tracing contacts. Bivariate analyses were performed to assess the risk factors for a high CFR and determine the time from rash onset until death. Each factor's contribution to the CFR was determined through multivariate logistic regression. From the number of measles cases and deaths found in the study we calculated the total number of measles cases and deaths for all of Nepal during the study period and in 2004. We identified 4657 measles cases and 64 deaths in the study period and area. This yielded a total of about 82 000 cases and 900 deaths for all outbreaks in 2004 and a national CFR of 1.1% (95% confidence interval, CI: 0.5-2.3). CFR ranged from 0.1% in the eastern region to 3.4% in the mid-western region and was highest in politically insecure areas, in the Ganges plains and among cases < 5 years of age. Vitamin A treatment and measles immunization were protective. Most deaths occurred during the first week of illness. To our knowledge, this is the first CFR study based on a nationally representative sample of measles outbreaks. Routine surveillance and studies of a single outbreak may not yield an accurate nCFR. Increased fatalities associated with political insecurity are a challenge for health-care service delivery. The short period from disease onset to death and reduced mortality from treatment with vitamin A suggest the need for rapid, field-based treatment early in the outbreak.

Sensitivity and specificity of multimodal and ultrasound screening for ovarian cancer, and stage distribution of detected cancers: results of the prevalence screen of the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS)

Ovarian cancer has a high case-fatality ratio, with most women not diagnosed until the disease is in its advanced stages. The United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) is a randomised controlled trial designed to assess the effect of screening on mortality. This report summarises the outcome of the prevalence (initial) screen in UKCTOCS. Between 2001 and 2005, a total of 202 638 post-menopausal women aged 50-74 years were randomly assigned to no treatment (control; n=101 359); annual CA125 screening (interpreted using a risk of ovarian cancer algorithm) with transvaginal ultrasound scan as a second-line test (multimodal screening [MMS]; n=50 640); or annual screening with transvaginal ultrasound (USS; n=50 639) alone in a 2:1:1 ratio using a computer-generated random number algorithm. All women provided a blood sample at recruitment. Women randomised to the MMS group had their blood tested for CA125 and those randomised to the USS group were sent an appointment to attend for a transvaginal scan. Women with abnormal screens had repeat tests. Women with persistent abnormality on repeat screens underwent clinical evaluation and, where appropriate, surgery. This trial is registered as ISRCTN22488978 and with ClinicalTrials.gov, number NCT00058032. In the prevalence screen, 50 078 (98.9%) women underwent MMS, and 48 230 (95.2%) underwent USS. The main reasons for withdrawal were death (two MMS, 28 USS), non-ovarian cancer or other disease (none MMS, 66 USS), removal of ovaries (five MMS, 29 USS), relocation (none MMS, 39 USS), failure to attend three appointments for the screen (72 MMS, 757 USS), and participant changing their mind (483 MMS, 1490 USS). Overall, 4355 of 50 078 (8.7%) women in the MMS group and 5779 of 48 230 (12.0%) women in the USS group required a repeat test, and 167 (0.3%) women in the MMS group and 1894 (3.9%) women in the USS group required clinical evaluation. 97 of 50 078 (0.2%) women from the MMS group and 845 of 48 230 (1.8%) from the USS group underwent surgery. 42 (MMS) and 45 (USS) primary ovarian and tubal cancers were detected, including 28 borderline tumours (eight MMS, 20 USS). 28 (16 MMS, 12 USS) of 58 (48.3%; 95% CI 35.0-61.8) of the invasive cancers were stage I/II, with no difference (p=0.396) in stage distribution between the groups. A further 13 (five MMS, eight USS) women developed primary ovarian cancer during the year after the screen. The sensitivity, specificity, and positive-predictive values for all primary ovarian and tubal cancers were 89.4%, 99.8%, and 43.3% for MMS, and 84.9%, 98.2%, and 5.3% for USS, respectively. For primary invasive epithelial ovarian and tubal cancers, the sensitivity, specificity, and positive-predictive values were 89.5%, 99.8%, and 35.1% for MMS, and 75.0%, 98.2%, and 2.8% for USS, respectively. There was a significant difference in specificity (p<0.0001) but not sensitivity between the two screening groups for both primary ovarian and tubal cancers as well as primary epithelial invasive ovarian and tubal cancers. The sensitivity of the MMS and USS screening strategies is encouraging. Specificity was higher in the MMS than in the USS group, resulting in lower rates of repeat testing and surgery. This in part reflects the high prevalence of benign adnexal abnormalities and the more frequent detection of borderline tumours in the USS group. The prevalence screen has established that the screening strategies are feasible. The results of ongoing screening are awaited so that the effect of screening on mortality can be determined.

Sporadic community-acquired Legionnaires' disease in France: a 2-year national matched case-control study

Legionnaires' disease (LD) is an aetiology of community-acquired bacterial pneumonia in adults, with a high case-fatality ratio (CFR). We conducted a matched case-control study to identify risk factors for sporadic, community-acquired LD. Cases of sporadic, community-acquired and biologically confirmed LD, in metropolitan France from 1 September 2002 to 31 September 2004, were matched with a control subject according to age, sex, underlying illness and location of residence within 5 km. We performed a conditional logistic regression on various host-related factors and exposures. Analysis was done on 546 matched pairs. The CFR was 3.5%. Age ranged from 18-93 years (mean 57 years), with a 3.6 male:female sex ratio. Cases were more likely to have smoked with the documentation of a dose-effect relation, to have travelled with a stay in a hotel (OR 6.1, 95% CI 2.6-14.2), or to have used a wash-hand basin for personal hygiene (OR 3.5, 95% CI 1.6-7.7) than controls. Tobacco and travel have been previously described as risk factors for LD, but this is the first time that such a dose-effect for tobacco has been documented among sporadic cases. These findings will provide helpful knowledge about LD and help practitioners in identifying patients at high risk.

A national stroke quality register: 12 years experience from a participating hospital

Registration of all hospitalized stroke patients is practiced in Sweden in order to assess care quality. Data in this register, Riks-Stroke (RS), may be biased due to incomplete registration. The purpose of this paper was to report changes in stroke outcome in relation to fluctuations in registration. Patients registered in RS at a hospital during the period 1994-2005 were analyzed. Case fatality at 28 days, living conditions, and activities of daily living (ADL) performance at 3 months were correlated to the number of patients registered and follow-up frequency. A total of 4994 stroke cases were registered during the period. A high annual registration rate was significantly correlated to a high case fatality ratio. A low annual follow-up rate was associated with a low proportion of patients living in their own home without any need of help. Quality parameters are sensible for selection bias, which make them difficult to compare over time and between hospitals. We suggest that by weighing outcome data against stroke severity, safer conclusions may be drawn. Additionally, hospitals considering setting up quality registers should make every effort to attain complete case ascertainment at all times, including patients managed outside the hospital, in order to avoid selection bias.

Hospital Surveillance of Rotavirus Infection and Nosocomial Transmission of Rotavirus Disease Among Children in Guinea-Bissau

Vaccination against rotavirus is protective against severe disease. Surveillance of rotavirus infection in developing countries might direct vaccination policy more efficiently. We implemented WHO's generic protocols for hospital-and community-based surveillance of rotavirus gastroenteritis. From April 2001 to May 2002, and from January 2003 to June 2003, we conducted hospital surveillance for rotavirus infection at the only pediatric ward in the capital of Guinea-Bissau. Children less than 5 years of age admitted with diarrhea or developing diarrhea during hospitalization were enrolled in the study. Rotavirus infection was detected in the feces samples using an ELISA assay. Rectal swabs were also obtained and its use was validated against stool specimen. During the surveillance period, 161 cases of rotavirus infection were registered. During the season, rotavirus accounted for 35% of all hospitalized diarrhea cases. The rate of nosocomial disease was 1.6 per 1000 child-days (95% confidence interval [CI] = 1.02-2.51) with high rates for children aged 12 to 23 months of age (rate: 3.09; 95% CI = 1.47-6.48). Most of the rotavirus cases (93%) were in children less than 2 years of age and only 10 children aged less than 3 months were infected. Fever (risk ratio (RR) 1.56; 95% CI = 1.16-2.10) and vomiting (RR 1.38; 95% CI = 1.11-1.73) were more common in patients with rotavirus than in patients with nonrotavirus diarrhea. The case-fatality was 8%. Results from stool samples and rectal swabs were concordant in 96% of the pairs. Rectal swabs increased the detection of rotavirus cases by 6% and deaths by 33% over stool sample results. Rotavirus infections were confined to a 4-month period each year. It is an important cause of childhood diarrhea with high case-fatality ratio in Guinea-Bissau. The use of rectal swab appeared to increase the detection rate of rotavirus infection and the case-fatality rate. The high rate of nosocomial infections in hospitalized children emphasizes the need for prevention of disease.

IS1301Fingerprint Analysis ofNeisseria meningitidisStrains Belonging to the ET-15 Clone

Meningococci of the ET-15 clone frequently cause clusters of invasive meningococcal disease (IMD) and are associated with a high case-fatality ratio. Timely typing of strains from outbreaks of IMD caused by this clone is hampered by the low variability of its surface antigens. We present a new Southern blot-based typing method for ET-15 meningococci based on the insertion element IS1301, which was present in all 70 ET-15 strains tested. Fingerprints were stable in vitro over a period of 100 days of cultivation on agar plates. The discriminatory power of IS1301 fingerprinting exceeded that of typing by serogrouping and antigen sequencing of the outer membrane proteins PorA and FetA, as determined by the analysis of 52 epidemiologically unrelated strains. In addition, the method provided conclusive results with regard to the comparison of strains from clusters of IMD. The investigation of insertion sites of IS1301 revealed several new intragenic insertions, among others, into open reading frames homologous to mafB and tspB. A previously described insertion in nadA was present in more than two-thirds of the strains analyzed, suggesting that NadA is probably an unreliable vaccine candidate for the prevention of ET-15 disease.

Polymerase chain reaction in comparison with serological tests for early diagnosis of human leptospirosis

The aim of this study was to compare the sensitivity and specificity of polymerase chain reaction (PCR) using two primer pairs and combined with blood culture, immunoglobulin M enzyme-linked immunosorbent assay (IgM ELISA), microscopic agglutination test (MAT) and slide agglutination test (SAT) in the diagnosis of human leptospirosis. We analysed 124 serum samples: 60 from patients with confirmed leptospirosis, 20 from patients with other diseases and 44 from healthy individuals. Analysing the first serum sample collected during the first 3-8 days of disease, the sensitivities of the four tests MAT, IgM ELISA, SAT and PCR were, respectively, 69.0%, 79.3%, 72.4% and 62%. In subsequent samples, those same sensitivities were, respectively, 95.4%, 100%, 100% and 72.7% in samples collected from days 9 to 14 and 88.9%, 88.9%, 77.8% and 44.4% in those collected from days 15 to 42. The most specific method (at 100%) was PCR and the least specific (at 89.1%) was IgM ELISA. Although we found PCR to be less sensitive than the serological tests over the course of the disease, our data indicate that PCR was the most sensitive in those initial serum samples presenting no specific antibodies detectable by any of the serological methods tested. We also recommend that PCR can be used in combination with serological tests as we found that this improves the sensitivity of the diagnosis of leptospirosis in the first phase of the disease (93.1-96.5%).

High Mortality Associated with an Outbreak of Hepatitis E among Displaced Persons in Darfur, Sudan

Hepatitis E virus (HEV) causes acute onset of jaundice and a high case-fatality ratio in pregnant women. We provide a clinical description of hospitalized case patients and assess the specific impact on pregnant women during a large epidemic of HEV infection in a displaced population in Mornay camp (78,800 inhabitants), western Darfur, Sudan. We reviewed hospital records. A sample of 20 clinical cases underwent laboratory confirmation. These patients were tested for immunoglobulin G (IgG) and immunoglobulin M (IgM) antibody to HEV (serum) and for amplification of the HEV genome (serum and stool). We performed a cross-sectional survey in the community to determine the attack rate and case-fatality ratio in pregnant women. Over 6 months, 253 HEV cases were recorded at the hospital, of which 61 (24.1%) were in pregnant women. A total of 72 cases (39.1% of those for whom clinical records were available) had a diagnosis of hepatic encephalopathy. Of the 45 who died (case-fatality ratio, 17.8%), 19 were pregnant women (specific case-fatality ratio, 31.1%). Acute hepatitis E was confirmed in 95% (19/20) of cases sampled; 18 case-patients were positive for IgG (optical density ratio > or =3), for IgM (optical density ratio >2 ), or for both, whereas 1 was negative for IgG and IgM but positive for HEV RNA in serum. The survey identified 220 jaundiced women among the 1133 pregnant women recorded over 3 months (attack rate, 19.4%). A total of 18 deaths were recorded among these jaundiced pregnant women (specific case-fatality ratio, 8.2%). This large epidemic of HEV infection illustrates the dramatic impact of this disease on pregnant women. Timely interventions and a vaccine are urgently needed to prevent mortality in this special group.

Influenza: the next pandemic?: a review

To examine existing information on the recent influenza outbreaks in order to create awareness of a possible influenza pandemic and to suggest future research areas in developing control strategies in Kenya. Review of literature via Internet, articles, journals and un-refereed features from the media and personal communications. Most published data from 1979 to March 2005 found to reveal cases of influenza outbreaks were included in the review. Also, selected articles on the recent outbreaks and professional guidance on influenza infections were critically examined and analyzed. Abstracts and articles identified were accessed, read to establish relevance to this review. Important points were prioritised and then included as subtitles; below each subtitle, published works were included. Finally, a table of influenza outbreaks and the strains of the viruses involved were drawn as summary. Influenza is a highly contagious, acute respiratory disease that may spread rapidly and pervasively through a population. Due to the diversity of susceptible reservoirs of influenza viruses and the interspecies transmission recently reported, a mutated strain of the virus to which people have no immunity could cause an influenza pandemic once the virus gains efficient and sustained human-to-human transmission. The fear that avian influenza could be a precursor to the next pandemic is real and inevitable, given the extremely high case-fatality ratio among confirmed cases and that genetic sequencing of influenza A (H5N1) viruses from human cases in Thailand and Vietnam show resistance to the antiviral medication amantadine and rimantadine. This calls for a high level of preparedness to avoid a public health emergency. Nowhere is this paradigm more real than in Africa.