following detection of pandemic ( h1n1 ) 2009 virus in 2 patients in california , usa , in april 2009 , the kenyan ministry of health intensified surveillance at 26 existing influenza sentinel surveillance sites where surveillance was being conducted for influenza - like illness and severe acute respiratory illness . an additional 29 hospitals and clinics in the country were trained to conduct surveillance for these conditions . a hospitalized case - patient with pandemic ( h1n1 ) 2009 was defined as a patient hospitalized for > 24 hours with acute respiratory illness who had an oropharyngeal or nasopharyngeal swab specimen positive for pandemic ( h1n1 ) 2009 virus by real - time reverse transcription pcr at either the kenya medical research institute ( kemri)/national influenza center laboratory , or the kemri / centers for disease control and prevention , kenya laboratory . we reviewed all available medical records for hospitalized patients with laboratory - confirmed pandemic ( h1n1 ) 2009 using a standardized case report form that included demographic , clinical , laboratory , and epidemiologic information . for hospitalization duration calculation , the day of admission was hospital day 0 . for patients for whom height and weight measurements were available , the body - mass index ( bmi , weight in kilograms divided by the square of height in meters ) was calculated . obesity was defined as a bmi > 30 in adults > 18 years old ( 3 ) . from june 29 , 2009 , when pandemic ( h1n1 ) 2009 infection was confirmed in kenya , through november 29 , 2009 , 690 patients with laboratory - confirmed pandemic ( h1n1 ) 2009 were identified . of these patients , 88 ( 13% ) most hospitalizations ( 61 [ 69% ] ) occurred during october and november ( figure ) . thirty - four ( 39% ) patients were < 2 years , and 19 ( 22% ) were 1849 years ( table ) . pandemic ( h1n1 ) 2009 case - patients hospitalized by week , kenya , july no significant differences were found in median age ( 7 years vs. 3 years ; p = 0.39 ) or sex ( 51% females vs. 54% females ; p = 0.40 ) between patients with clinical data and patients without clinical data . the 49 case - patients were from 4 public and 3 private hospitals in 4 of kenya s 8 provinces . half ( 51% ) of case - patients were admitted to siaya district hospital in nyanza province . of 20 patients with known hiv infection status , 4 ( 20% ) were hiv positive . the median duration between onset of symptoms and hospitalization was 3 days ( range : 014 days ) . the most common symptoms at admission were self - reported fever ( 43 patients [ 88% ] ) , cough ( 45 patients [ 92% ] ) , and vomiting ( 20 patients [ 41% ] ) . eighteen ( 37% ) patients reported diarrhea . of 22 patients with malaria blood smear results , 5 ( 23% ) had positive results ( median patient age 5 months ) . of 42 patients with data on antiviral treatment , 10 ( 24% ) had received oseltamivir either before or during hospitalization . the first was a 55-year - old hiv - negative man without underlying illness who had been admitted with acute respiratory illness . he was transferred to the intensive care unit after secondary bacterial infection ( pseudomonas aeruginosa ) developed . the patient died after 45 days while receiving mechanical ventilation in the intensive care unit . the next person who died was a 4-year - old boy without underlying illness ( hiv status unknown ) who had been admitted with a cough , vomiting , and fever . this study describes the epidemiology , clinical features , and clinical course of pandemic ( h1n1 ) 2009 infections in hospitalized patients in a sub - saharan african country outside south africa . the large proportion of pandemic ( h1n1 ) 2009 hospitalizations among young adults in kenya is consistent with findings from new zealand , the united states , and australia ( 46 ) . however , the median age of 5.1 years is lower than median ages found in australia ( 15 years ) and the united states ( 20 years ) ( 4,5 ) . the lower median age in kenya could be explained by varying patterns of health care use by age in kenya . studies in western kenya and nairobi have shown that adults are less likely to seek medical care at hospitals for acute respiratory illness than are young children ( 7,8 ) . one fourth of those hospitalized with pandemic ( h1n1 ) 2009 influenza in kenya had an underlying medical condition , a lower proportion than in the united states ( 73% ) , ireland ( 50% ) , and chile ( 37% ) ( 5,9,10 ) . this difference could be due to undetected chronic illnesses ; in many health care facilities in kenya , patients are not routinely screened for chronic diseases . twenty percent of hospitalized pandemic ( h1n1 ) 2009 patients with available hiv data were positive for the virus . although this percentage is higher than the national hiv prevalence ( 7% ) ( 11 ) , the hiv - positive patients were all from nyanza province , which has an hiv prevalence of 15% ( 11 ) . nevertheless , our findings suggest that hiv patients could be at risk for severe pandemic ( h1n1 ) 2009 influenza , supporting results of a study in south africa which reported that 53% of pandemic ( h1n1 ) 2009 patients who died were hiv positive ( 12 ) . however , our report included a relatively small number of patients who had been tested for hiv , and cd4 counts and information on use of antiretroviral drugs were unavailable . the proportion of hospitalized pandemic ( h1n1 ) 2009 patients who were obese ( 20% ) is higher than the estimates of the prevalence ( 5%10% ) of obesity in adults in kenya ( 13 ) . these findings are consistent with recent studies in the united states that have shown obesity to be a risk factor for severe outcomes from pandemic ( h1n1 ) 2009 ( 14 ) . although 50,000 treatment courses of oseltamivir were available in kenya in may 2009 , oseltamivir was underused during the study period , likely because laboratory confirmation of pandemic ( h1n1 ) 2009 was not available quickly enough to inform patient management . in addition , clinicians may not have been aware of the availability of and indications for oseltamivir . the kenya ministry of health has recommended and made available oseltamivir for empirical treatment of hospitalized patients with suspected pandemic ( h1n1 ) 2009 ( 15 ) . the reported cases therefore may not be representative of all hospitalized persons with pandemic ( h1n1 ) 2009 in kenya . in addition , reported cases were limited to hospitals where influenza surveillance was conducted and hospitals where clinicians were aware that pandemic ( h1n1 ) 2009 testing was available . most kenyan hospitals have not been conducting systematic surveillance for pandemic ( h1n1 ) 2009 ; thus , hospitalized patients with pandemic ( h1n1 ) 2009 were likely missed . existing and enhanced sentinel hospital surveillance for influenza in kenya made it possible to describe severe outcomes of pandemic ( h1n1 ) 2009 in this country . continued surveillance is essential in clarifying the full clinical spectrum and evolution of the pandemic in kenya , including the role of coexisting conditions such as hiv infection and malaria . in addition , increasing clinician awareness of pandemic ( h1n1 ) 2009 treatment guidelines could improve patient management .
to describe the epidemiology and clinical course of patients hospitalized with pandemic ( h1n1 ) 2009 in kenya , we reviewed medical records of 49 such patients hospitalized during july 
 november 2009 . 
 the median age ( 7 years ) was lower than that in industrialized countries . 
 more patients had hiv than the general kenyan population .