Effectiveness of pandemic and seasonal influenza vaccines in preventing pandemic influenza-associated hospitalization

Vaccines are leading pharmacological measures for limiting the impact of pandemic influenza in the community. The objective of this study was to investigate the effectiveness of influenza (pandemic and seasonal) vaccines in preventing pandemic influenza-associated hospitalization. We conducted a multicenter matched case-control study in 36 Spanish hospitals. Patients hospitalized with confirmed pandemic influenza between November 2009 and February 2010 and two hospitalized controls per case, matched according to age, date of hospitalization and province of residence, were selected. Multivariate analysis was performed using conditional logistic regression. Subjects were considered vaccinated if they had received the vaccine >14 days (seasonal influenza vaccine) or >7 days (pandemic influenza vaccine) before the onset of symptoms (cases) or the onset of symptoms of the matched case (controls). For the pandemic influenza vaccine, vaccination effectiveness (VE) was estimated taking into account only patients recruited from November 23, 2009, seven days after the beginning of the pandemic influenza vaccination campaign. 638 cases and 1250 controls were included. The adjusted VE of the pandemic vaccine in the ≥18 years age group was 74.2% (95% CI, 29-90) and that of the influenza seasonal vaccine 15.0% (-34 to 43). The recommendation of influenza vaccination should be reinforced as a regular measure to reduce influenza-associated hospitalization during pandemics and seasonal epidemics.     

肺部感染患者住院期间发生急性左心力衰竭的危险因素分析

目的探讨肺部感染患者住院期间发生急性左心力衰竭的危险因素,并采取相应的干预措施。方法回顾性分析2014年1月至2019年3月期间我院200例肺部感染住院患者的临床资料,根据患者住院期间是否发生急性左心力衰竭将其分为心衰组(35例)和非心衰组(165例),对肺部感染患者住院期间发生急性左心力衰竭因素进行单因素和多因素Logistic回归分析。结果200例肺部感染患者的血培养致病菌阳性率为30.5%(61例),以革兰氏阴性菌和革兰氏阳性菌为主。单因素分析显示,急性左心力衰竭发作与年龄、pro-BNP水平、心脏增大证据、高血压、心衰发作史或AMI史均有相关性(P<0.05),而与性别、糖尿病史、肾功能不全、联用抗生素、补液量无相关性(P>0.05)。Logicstics回归分析显示,年龄、补液速度、高血压、心衰发作史或AMI史是肺部感染患者发生急性左心力衰竭的相关危险因素(P<0.05)。监测pro-BNP水平,控制血压,对高龄、有心衰发作史或AMI史的患者注意利尿,控制补液速度,予以调节神经体液因素口服药为防止急性左心力衰竭发作的保护因素。结论肺部感染患者发生急性左心力衰竭的危险因素较多,主要为年龄、高血压、心衰发作史或AMI史、补液速度,临床上应采取相应措施预防肺部感染患者在住院期间发生急性左心力衰竭。     

Effectiveness of H1N1/09 monovalent and trivalent influenza vaccines against hospitalization with laboratory-confirmed H1N1/09 influenza in Australia: a test-negative case control study

We aimed to estimate the effectiveness of H1N1/09 containing influenza vaccines against hospitalization from influenza in Australia. We performed a test-negative case control study in patients hospitalized in 15 sentinel Australian hospitals between March and November 2010, comparing influenza vaccination (H1N1/09 monovalent or 2010 seasonal trivalent) in hospitalized patients with PCR-confirmed influenza compared to PCR-negative controls. Between March and November 2010, 1169 hospitalized patients were tested for suspected influenza, of which influenza vaccine status was ascertained in 165/238 patients with H1N1/09 influenza, 40/64 with seasonal influenza and 558/867 test negative controls; 24% of H1N1/09 cases, 43% of seasonal influenza cases and 54% of controls were vaccinated. VE against hospitalisation with H1N1/09 influenza after adjusting for age, medical comorbidities and pregnancy status was estimated at 49% (95% CI: 13%, 70%). Influenza vaccination was associated with a reduction in hospitalisation caused by H1N1/09 influenza in the 2010 southern hemisphere winter season.     

Effectiveness of the influenza vaccine at preventing hospitalization due to acute lower respiratory infection and exacerbation of chronic cardiopulmonary disease in Korea during 2010–2011

Background

Influenza epidemics are accompanied by a considerable increase in hospitalization due to acute lower respiratory infection and exacerbation of underlying medical conditions. We estimated the effectiveness of the influenza vaccine at preventing hospitalization due to acute lower respiratory infection and new onset or acute exacerbation of chronic cardiopulmonary disease.

Method

During the peak influenza period in 2010–2011, we performed a multicenter, case–control, retrospective cohort study of patients who were hospitalized due to newly developed pneumonia, bronchitis, and bronchiolitis, or new onset or acute exacerbation of asthma, COPD, ischemic heart disease, and CHF. Controls were selected from outpatients who visited study hospitals but who were not hospitalized during the same study period. Controls were matched 1:1 to cases based on age, gender, and date of hospital visit. Univariate and multivariate logistic regression analyses were used to determine the effectiveness of the influenza vaccine at decreasing hospitalization.

Results

Between December 2010 and February 2011, 556 hospitalized subjects were identified. Age, gender, and body mass index (BMI) were similar between case and control groups. The influenza vaccination rate of the hospitalized and non-hospitalized patients was 42.4% and 52.2%, respectively (p < 0.001). The overall vaccine effectiveness for preventing hospitalization was 32.5% (odds ratio 0.675, 95% confidence interval [CI] 0.486–0.937; p = 0.019). Multivariate logistic analysis showed that influenza vaccination significantly reduced the risk of hospitalization, especially due to new onset or acute exacerbation of ischemic heart disease and CHF in patients aged 65 years and older (OR 0.274, 95% CI 0.114–0.658, p = 0.004). The estimated vaccine effectiveness in these patients was 72.6%.

Conclusion

Influenza vaccination reduced the rate of hospitalization among patients with underlying chronic heart disease, particularly those patients 65 years old and greater.     

Is the adjuvanted influenza vaccine more effective than the trivalent inactivated vaccine in the elderly population? Results of a case–control study

Introduction

Influenza illness is an important public health problem and annual vaccination is globally recommended for high risk populations.

Objective

The aim was to evaluate and compare the effectiveness of influenza vaccines in reducing hospitalizations for influenza or pneumonia during two influenza seasons in the elderly.

Methods

A case–control study was performed, using administrative database of the Local Health Unit Roma-A (LHU RM-A). The included subjects were at least 65 years old and residing in one of the four districts of the LHU. The cases were hospitalized for influenza or pneumonia during influenza season in the years 2010–2011 and 2011–2012. The controls were hospitalized in the same period, but not for influenza or pneumonia. The subjects were immunized with the trivalent inactivated influenza vaccine (TIV) in the first influenza season (2010–2011) and with the adjuvanted influenza vaccine MF59 (ATIV) in the second season (2011–2012).

Results

A total of 269 cases and 1247 controls were included for the 2010–2011 influenza season, and 365 cases and 1227 controls were selected for the 2011–2012 season. Up to 63.6% cases and 53.5% controls in the 2010–2011 season and 78.6% of cases and 64.1% of controls in the 2011–2012 season have not been vaccinated. Female gender and high educational level were protective factors for hospitalization. Subjects over 75 years were at high risk of hospitalization compared to 65–74 years olds. Influenza vaccination reduced significantly hospitalization in both seasons. In subjects with 65–74 years TIV was more effective than ATIV; vice versa for those over 75 years old.

Discussion and conclusion

TIV and ATIV reduce hospitalization for influenza or pneumonia with a variable degree of protection in different age groups. In particular, ATIV is more effective in individuals over 75 years old.     

1983-2002年慢性心力衰竭住院患者的病因分析

目的了解近20年慢性心力衰竭住院患者病因构成的变化.方法收集1983-2002年天津市一中心医院心脏内科,出院诊断为慢性心力衰竭的住院患者1 259例.以1983-1992年的患者为前10 a组,以1993-2002年的病例为后10 a组,比较分析两组原发、共患和多病因的构成.结果前10 a组原发病因为冠心病的构成比低于后10 a组,肺心病和高血压性心脏病高于后10 a组,差别均有统计学意义（P＜0.05）.共患病因排序依次为高血压（44.00%）、糖尿病（16.4%）、慢性阻塞性肺病（COPD,14.3%）、脑血管病（11.4%）、贫血（5.2%）.与前10a组比较,后10a组COPD共患病因减少（χ^2=45.22;P＜0.000 1）,其余共患病因均增加（P＜0.01）.前10 a组以单病因比例为多,后10 a组以多病因比例为多（P＜0.0001）.2种病因组合比例最高的为冠心病合并高血压,占33.8%;3种病因组合比例最高的为冠心病、高血压及糖尿病,占8.4%.结论慢性心力衰竭住院患者首位原发病因是冠心病,高血压、糖尿病、COPD是最常见的共患病因,后10 a组多病因合并比例显著高于前10 a组.     

Conventional influenza vaccination is not associated with complications in working-age patients with asthma or chronic obstructive pulmonary disease

By using a nested case-control design, the authors studied the effectiveness of the influenza vaccine in reducing severe and fatal complications in 4,241 and 5,966 primary care, working-age patients aged 18-64 years who had asthma or chronic obstructive pulmonary disease during the 1998-1999 and 1999-2000 influenza epidemics in the Netherlands. Patients developing fatal or nonfatal exacerbations of lung disease, pneumonia, congestive heart failure, or myocardial infarction during either epidemic were considered cases. For each case, four age- and sex-matched controls were randomly sampled, and patient records were reviewed. Conditional logistic regression and propensity scores were used to assess vaccine effectiveness after adjustment for confounding factors. In seasons one and two, respectively, 87% (47/54) and 85% (171/202) of the cases and 74% (155/210) and 75% (575/766) of the controls had been vaccinated. After adjustments, vaccination was not associated with reductions in complications (season one: odds ratio = 0.95, 95% confidence interval (CI): 0.26, 3.48; season two: odds ratio = 1.07, 95% CI: 0.59, 1.96; pooled odds ratio = 1.07, 95% CI: 0.63, 1.80). Because influenza vaccination appeared not to be associated with a clinically relevant reduction in severe morbidity, other measures need to be explored.     

Vaccine effectiveness in preventing influenza hospitalizations in Navarre, Spain, 2010-2011: cohort and case-control study

We evaluated the 2010-2011 seasonal influenza vaccine effectiveness in preventing hospitalizations. Using healthcare databases we defined the target population for vaccination in Navarre, Spain, consisting of 217,320 people with major chronic conditions or aged 60 years and older. All hospitalized patients with influenza-like illness (ILI) were swabbed for influenza testing. A total of 269 patients with ILI were hospitalized and 61 of them were found positive for influenza virus: 58 for A(H1N1)2009 and 3 for B virus. The incidence rates of hospitalization with laboratory-confirmed influenza were compared by vaccination status. In the Cox regression model adjusted for sex, age, children in the household, urban/rural residence, comorbidity, pandemic vaccination, pneumococcal vaccination, outpatient visits and hospitalization in the previous year, the seasonal vaccine effectiveness was 58% (95% CI: 16-79%). The nested test-negative case-control analysis gave an adjusted estimate of 59% (95% CI: 4-83%). These results suggest a moderate effect of the 2010-2011 seasonal influenza vaccine in preventing hospitalization in a risk population. The close estimates obtained in the cohort and the test-negative case-control analyses suggest good control of biases.     

Effectiveness of the influenza vaccine at reducing adverse events in patients with heart failure: A systematic review and meta-analysis

BackgroundThe association between influenza and adverse vascular events in patients with heart failure is well documented. The effect of the influenza vaccine on preventing such adverse events is uncertain. This systematic review and meta-analysis addressed whether vaccination against influenza reduces adverse vascular events and mortality in heart failure patients.MethodsMEDLINE and EMBASE databases were comprehensively searched, study screening and quality assessment were completed, and data was synthesized. Eligible studies investigated heart failure patients who received the influenza vaccine, and reported outcomes within 12 months, compared to heart failure patients who did not receive the influenza vaccine. The following 6 outcomes were assessed: all-cause mortality, cardiovascular-related mortality, all-cause hospitalization, cardiovascular-related hospitalization, non-fatal myocardial infarction, and non-fatal stroke. Risk of bias was assessed using the Newcastle-Ottawa Scale and a GRADE assessment was completed. A random-effects meta-analysis was performed to estimate the pooled risk ratio (RR), 95% confidence intervals (CIs), and heterogeneity using I² statistics.ResultsAfter synthesizing data from 7 non-randomized studies (247,842 patients), the results demonstrate the risk of all-cause mortality is significantly reduced within 12 months of a heart failure patient receiving the influenza vaccine (RR = 0.75, 95% CI 0.71–0.79; P<0.0001); very low certainty of evidence. The risk of cardiovascular-related mortality was significantly reduced (RR = 0.77, 95% CI 0.73–0.81; P<0.0001); low certainty of evidence. The pooled risk of all-cause hospitalization was higher among vaccinated heart failure patients (RR = 1.24, 95% CI 1.13–1.35; P<0.0001), based on two studies; very low certainty of evidence and considerable heterogeneity (I² = 90%). No eligible studies assessed cardiovascular-related hospitalization, non-fatal myocardial infarction, or non-fatal stroke.ConclusionsInfluenza vaccination appears to reduce adverse cardiovascular events, although the certainty of the evidence is low or very low. Rigorous randomized controlled trial evidence is needed to further examine the protective effect of the influenza vaccine in heart failure patients.     

A case-control study of elderly patients with acute respiratory illness: effect of influenza vaccination on admission to hospital in winter 2003-2004

Every winter, hospitals face a large increase in emergency respiratory admissions in elderly people. A case-control study was undertaken to assess the effect of routine influenza vaccine in preventing such admissions among a cohort of UK elderly presenting with acute respiratory illness during winter 2003-2004. 157 hospitalised cases and 639 controls (matched for age, sex and week of consultation) were interviewed. In a winter typical of levels of circulating influenza in recent years, influenza vaccine did not show a protective effect on emergency respiratory admissions overall (adjusted OR 1.2 (95%CI 0.8, 1.9). Policy makers should not rely solely on influenza vaccine routinely having a large effect on winter pressures, and should focus on additional preventive strategies.     

Risk factors of influenza (H1N1) 2009 hospitalization and effectiveness of pharmaceutical and nonpharmaceutical interventions in its prevention: a case-control study

Potentially useful pharmaceutical measures to limit the impact of pandemic influenza in the community include antiviral drugs (neuraminidase inhibitors) and the influenza and pneumococcal vaccines, as influenza predisposes to bacterial pneumonia caused by Streptococcus pneumoniae. Non-pharmaceutical measures include hand washing and respiratory hygiene. Due to the lack of knowledge of the effectiveness of these measures in a pandemic situation, in September 2009, CIBER de Epidemiología y Salud Pública presented a multicenter case-control study, with controls matched for age, hospital and date of hospitalization, to investigate these aspects in 37 hospitals in 7 Spanish autonomous communities, in response to the call for research projects by the Ministry of Science and Innovation Research Program on Influenza A (H1N1) in Spain. For each confirmed hospitalized case of pandemic influenza, 1 confirmed outpatient case and 3 controls (2 hospitalized and 1 outpatient) were selected. Demographic variables, underlying medical conditions, use of antiviral agents, vaccines received and hygiene habits were collected for all cases and controls. In hospitalized cases, information on antiviral therapy and disease progression was collected. A total of 3750 patients were recruited by October 2010. Data cleansing and the recovery of variables is now underway. The involvement of the Public Health Directorate has been instrumental in adapting the project to the evolution of the pandemic.     

慢性阻塞性肺疾病患者流感疫苗和23价肺炎球菌多糖疫苗接种研究进展

近年来国内外慢性阻塞性肺疾病（COPD）患者流感疫苗和23价肺炎球菌多糖疫苗（PPV23）接种有效性的相关研究发现,接种流感疫苗和PPV23可显著降低COPD患者的流感和肺炎感染风险,减少疾病的急性加重以及与之相关的住院,尤其是接种流感疫苗还可降低患者诱发缺血性心脏病、急性冠脉综合征、室性心律失常、肺癌、痴呆和死亡的风险,二者联合接种保护作用更加显著。国内外权威指南、共识均建议COPD患者接种流感疫苗和PPV23。目前国内流感疫苗和肺炎球菌疫苗接种率均偏低,且在COPD患者中的应用研究较少。应采取有效措施加强知识普及和指南宣传,提高疫苗接种率。同时还应进一步加强COPD患者接种流感和PPV23的临床研究,尤其是联合接种的临床效益分析,以切实改善COPD患者的生存现状和预后。     

Comparison of vaccine effectiveness against influenza hospitalization of cell-based and egg-based influenza vaccines, 2017–2018

Egg-based influenza vaccines could be less effective than cell-based vaccine due to adaptive mutations acquired for growth. We conducted a test-negative case-control study at Kaiser Permanente Southern California to assess vaccine effectiveness (VE) against hospitalization for laboratory-confirmed influenza during 2017–2018. Among the 1186 cases and 6946 controls, 74% and 59%, respectively, were ages ≥ 65 years. For any influenza, the adjusted relative VE of cell-based vaccine versus egg-based vaccines was 43% (95% CI: −45% to 77%) for patients ages < 65 years and 6% (95% CI: −46% to 39%) for patients ages ≥ 65 years. For influenza A(H3N2), the adjusted relative VE was 61% (95% CI: −63% to 91%) for patients ages < 65 years and −4% (95% CI: −70% to 37%) for patients ages ≥ 65 years. Statistically significant protection against influenza hospitalization of cell-based vaccine compared to egg-based vaccines was not observed, but further studies in additional influenza seasons are warranted.     

Effectiveness of inactivated influenza and COVID-19 vaccines in hospitalized children in 2022/23 season in Japan – The first season of co-circulation of influenza and COVID-19

We have analyzed the inactivated vaccine effectiveness (VE) for preventing influenza hospitalization by test-negative design in the 2022/23 season. This is the first season of co-circulation of influenza and COVID-19, and a unique period because all inpatients received COVID-19 screening. Among 536 children hospitalized with fever, none were positive for both influenza and SARS-CoV-2. The adjusted VE for preventing influenza A for all children, the 6–12-year-old group, and those with underlying diseases was 34 % (95 ％CI, −16 %–61 %, n = 474), 76 % (95 ％ CI, 21 %–92 %, n = 81), and 92 % (95 ％ CI, 30 %–99 %, n = 86), respectively. Only 1 out of 35 hospitalized cases with COVID-19, and 42 out of 429 controls, had been immunized with COVID-19 vaccine. This is the first report showing influenza VE by age group in children in this limited season. We still recommend the inactivated influenza vaccine for children based on the significant VE in subgroup analysis.     

重症监护病房中急性呼吸窘迫综合征的预后危险因素探讨

目的 探讨重症监护病房(ICU)中急性呼吸窘迫综合征(ARDS)的死亡率以及预后危险因素.方法 根据从2009年1月～2011年1月入住某院重症监护病房(ICU)中的急性呼吸窘迫综合征(ARDS)的230例患者,采用1992年欧美ARDS联席会议提议通过的ARDS诊断标准,对患者进行持续24h的治疗时间,并进行临床观察.结果 2009年1月～2011年1月入住的重症监护病房(ICU)中的急性呼吸窘迫综合征(ARDS)的230例患者,其中肺源性患者85例,肺外源性患者145例.在此治疗期间,采用APACHEII评分标准对死亡率进行调整,调整2年时间内死亡率没有明显变化(P=0.85),并且根据多方面因素的资料研究分析,ARDS死亡因素有很多,包括患者年龄、基础病理、多功能器官功能障碍妨碍住院时间的治疗,其中导致死亡率最高的因素就是脓毒性休克和心功能衰竭,死于呼吸衰竭的患者其实很少.结论 急性呼吸窘迫综合征(ARDS)是近两年来该院接收最常见的患者之一,也是死亡率比较高的急重病,脓毒性休克和心功能衰竭都是导致ARDS死亡率增高的主要原因.     

上海市松江区成人严重急性呼吸道感染住院病例流行病学特征分析

目的 了解上海市松江区成人严重急性呼吸道感染(severe acute respiratory infection,SARI)住院病例的流行病学特征及病原谱,探索新发传染病症状监测工作模式。方法 收集松江区某监测哨点医院2017年1月—2018年3月372例成人SARI住院病例监测资料,按照是否感染流感病毒,将病例分为流感组与非流感组,对流行病学及病原学特征等情况进行分析性描述。结果 共纳入372例SARI住院病例,SARI病例住院率4.15%,有夏季峰和冬季峰。发热、咳嗽、咳痰等是SARI住院病例最常见的临床症状,肺炎是最常见的并发症(48.66%),所有病例均未接种肺炎疫苗;流感组SARI病例数80例,流感病毒检测阳性率21.5%,其中甲型流感病毒占优势(56.25%);非流感组中其他病原体检出率为16.13%,以人肠病毒/鼻病毒的检出率最高(28.3%)。老年人在流感组中占比较高,差异有统计学意义(χ²=15.68,P<0.05);流感组的抗生素使用率较非流感组高,差异有统计学意义(χ²=27.73,P<0.05),非流感组呼吸衰竭的发生率较流感组高,差异有统计学意义(χ²=7.829,P<0.05)。结论 成人SARI病例监测的开展不仅是对新发传染病症状监测模式的探索实践,也对了解成人严重急性呼吸道感染的流行病学及病原学特征具有重要意义,建议提高老年人肺炎疫苗接种率以及流感病人临床抗病毒药物的使用。     

心力衰竭患者并发肺部感染的相关危险因素及治疗措施

目的 探讨心力衰竭患者并发肺部感染的相关危险因素及治疗措施,以降低肺部感染发生率.方法 选择2008年2月-2011年7月医院收治的心力衰竭患者80例,根据并发感染情况,分为感染组10例与非感染组70例,两组均采用药物联合治疗,同时对两组相关资料进行调查.结果 经过治疗后,非感染组临床有效率为97.5％,感染组有效率为95.0％,两组治疗效果均较好;肺部感染的发生与住院天数、年龄、曾经使用药物状况等因素密切相关(P＜0.05).结论 肺部感染常见于心力衰竭住院患者,住院天数、年龄、曾经使用药物是重要的发病危险因素,针对肺部感染发生的危险因素应采取有效的治疗措施以降低肺部感染发生率.     

Influenza vaccine effectiveness against hospitalization with laboratory-confirmed influenza in Greece: A pooled analysis across six seasons, 2013–2014 to 2018–2019

BackgroundMonitoring seasonal influenza Vaccine Effectiveness (VE) is key to inform vaccination strategies and sustain uptake. Pooling data across multiple seasons increases precision and allows for subgroup analyses, providing more conclusive evidence. Our aim was to assess VE against hospitalization with laboratory-confirmed influenza in Greece over six seasons, from 2013 to 2014 to 2018–2019, using routinely collected surveillance data.MethodsSwab samples from hospitalized patients across the country were tested for influenza by RT-PCR. We used the test-negative design, with patients testing positive for influenza serving as cases and those testing negative serving as controls. VE was calculated as one minus the Odds Ratio (OR) for influenza vaccination, estimated by mixed-effects logistic regression and adjusted for age, sex, hospitalization type (being in intensive care or not), time from symptom onset to swabbing, and calendar time. Stratified estimates by age and hospitalization type were obtained, and also subgroup estimates by influenza type/subtype and season. Antigenic and genetic characterization of a subset of circulating influenza strains was performed.ResultsA total of 3,882 test-positive cases and 5,895 test-negative controls were analyzed. Across all seasons, adjusted VE was 45.5% (95% CI: 31.6–56.6) against all influenza, 62.8% against A(H1N1)pdm09 (95% CI: 40.7–76.7), 28.2% against A(H3N2) (95% CI: 12.0–41.3) and 45.5% against influenza B (95% CI: 29.1–58.1). VE was slightly lower for patients aged 60 years and over, and similar between patients hospitalized inside or outside intensive care. Circulating A(H1N1)pdm09 and B strains were antigenically similar to the vaccine strains, whereas A(H3N2) were not.ConclusionOur results confirm the public health benefits from seasonal influenza vaccination, despite the suboptimal effectiveness against A(H3N2) strains. Continued monitoring of VE is essential, and routinely collected surveillance data can be valuable in this regard.     

Prognostic factors of hospital mortality from diarrhea or pneumonia in infants younger than 1 year old. A case-control study]

Diarrhea and pneumonia are common diseases in children aged under one year, for which there are simple therapeutic measures. However, infant mortality due to these diseases is still very high, varying markedly according to socio-economic status. The characteristics of children who died (cases) and of those who were hospitalized with diarrhea or pneumonia, but survived (controls), were studied. The following groups of variables were studied: socio-economic, environmental and biological conditions, nutritional status and breast-feeding. Information on cases and controls was collected from hospital records and through home interviews. Important losses occurred in the latter: 40% of cases and 50% of controls were not interviewed. There were no significant differences between cases who were included and those who were not, in terms of age, sex or place of residence. To estimate relative risks of prognostic factors unconditional Logistic Regression was used to calculate the odds ratios and their 95% confidence intervals. Prematurity, low birth weight, weight/age deficit, presence of edema and poor general status at hospital admission were prognostic factors for hospital case-fatality. In relation to the anthropometric variables, it was not possible to conclude for certain whether the increased case-fatality was linearly or non-linearly (threshold) associated with nutritional deficit. The duration of breast-feeding was only associated with case-fatality for pneumonia. Socio-economic factors were not important for the prognosis of children admitted to hospital with diarrhea or pneumonia. Some of the expected risk factor associations were not detected, maybe due to the small sample size (resulting from the high losses) which was insufficient to show small differences. In this study the biological conditions of children with diarrhea or pneumonia appeared to be the important prognostic factors for hospital case-fatality.