on september 23 , 2014 , a healthcare worker was admitted to mengo hospital in kampala , uganda , with a febrile illness suspected to be viral hemorrhagic fever ( vhf ) . the patient , a 30-year - old man , was a radiographer who worked at mengo hospital and part - time at mpigi health center iv in the mpigi district , 30 km south of kampala ( figure 1 ) . a rapid diagnostic test result was positive for malaria , and the patient was given intravenous ceftriaxone , 5% dextrose , and artesunate . however , his condition continued to deteriorate .   locations where patient with confirmed marburg virus disease lived , worked , and was buried , kampala , uganda , 2014 . clinical findings included fever ( temperature 38.4c ) , nausea , vomiting , diarrhea , musculoskeletal pain , abdominal pain , headache , sore throat , difficulty swallowing , difficulty breathing , anorexia , bleeding from the nose , bloody stools , vomiting blood , and upper gastrointestinal tract bleeding . whole blood and serum samples collected on september 28 were sent to the uganda virus research institute ( uvri)/us centers for disease control and prevention ( cdc ) vhf laboratory in entebbe for testing on september 30 . we performed diagnostic testing by real - time reverse transcription pcr ( rt - pcr ) targeting the marv np gene , antigen detection , and marv igm elisa on the suspected sample as described ( 8) . we detected marv by rt - pcr , but antigen detection and igm serologic results were negative . we obtained independent confirmation from duplicate whole blood and serum samples by using rt - pcr primers and probes targeting marv vp40 gene and a commercial filovirus pcr screening assay ( altona diagnostics , hamburg , germany ) ( 9 ) ( table ) . on the basis of the positive rt - pcr results , we confirmed mvd in this patient . we shipped specimens to the cdc viral special pathogens branch , division of high - consequence pathogens and pathology , national center for emerging and zoonotic infectious diseases ( atlanta , ga , usa ) , for further testing , including virus isolation and sequencing . a virus isolate ( 812601 ) was generated from the clinical specimen after a single passage in cell culture ( vero e6 ) . after laboratory confirmation , a multidisciplinary team from uvri and cdc - uganda performed the initial outbreak investigations at mengo hospital and mpigi health center iv . the investigation team provided the outbreak case definition , and details of case contacts were obtained from both health facilities . an investigation was also performed in kasese district , where the health worker was taken for burial . in addition , an ecologic investigation was conducted to identify roosting sites nearby for the potential presence of r. aegyptiacus bats . we created an outbreak database by using the epi info viral hemorrhagic fever outbreak management application ( 10 ) . all case and contact data were managed by the uganda ministry of health public health emergency operations center . we identified 197 close contacts , who were followed for 21 days . during the course of follow - up , 33 ( 16.2% ) of the 197 contacts converted to suspected case - patients by exhibiting clinically compatible signs or symptoms matching the outbreak case definition . blood samples from suspected case - patients were tested at the uvri / cdc laboratory in entebbe ; all were negative for marv by rt - pcr and serologic analysis . we describe the second single - case filovirus outbreak detected in uganda ; a case of infection with sudan ebolavirus was reported in luwero district in 2011 ( 11 ) . the investigation was unable to identify a conclusive source of infection , including evidence of the natural reservoir host near where the infected patient was working or residing or potential cases in persons who visited health centers before this case was confirmed . the patient tested positive for malaria but later tested positive for marv by rt - pcr and serologic analysis . these findings indicate that co - infection of viral hemorrhagic fever ( vhf ) and other tropical infectious diseases can confound diagnosis and delay early detection , potentially resulting in large outbreaks that are much harder to control , as was seen during the 20142015 ebola virus outbreak in west africa ( 12 ) . this finding emphasizes the need for continued surveillance and awareness even when other , more common pathogens are initially suspected . the finding of no secondary cases in this investigation can be attributed , in part , to use of infection control practices and personal protective equipment when first encountering a suspected vhf case . because uganda has experienced 10 vhf outbreaks since 2011 , increased awareness and use of personal protective equipment and infection control practices have greatly limited secondary transmission , especially in the healthcare setting . routine use of gloves , protective gowns , and chlorine is now more common in lower - level healthcare facilities in uganda ; these protective products were used at both mengo hospital and mpigi health center iv . the full genomic sequence of this marv isolate ( 812601 ; genbank accession no . kp985768 ) falls into a cluster that consists mostly of marv sequences isolated from bats . the closest related sequence was obtained from marv isolated from a juvenile male r. aegyptiacus bat ( q843 ) captured in august 2009 in python cave , queen elizabeth national park ( figure 2 ) . other viral sequences from bat specimens in this clade were from bats collected from either python cave or the kitaka mine during 20072009 . the most closely related human sequence ( 01uga07 ) was from a miner who worked in the kitaka mine in july 2007 ( 3,7 ) . because of the wide genetic diversity of marvs , there is no definitive way to identify where this patient may have become infected . phylogenetic tree comparing complete or nearly complete marburg virus ( marv ) genomes sequenced from bat and human sources in uganda . a consensus whole - genome sequence was assembled by mapping reads to the reference marv sequence nc_001608 using clc genomics workbench ( waltham , ma , usa ) . viral sequences acquired from human sources are in standard type , and viral sequences acquired from bats are italicized ; the sequence from the human case - patient described in this study , mbg 812601 2014 , is in bold . evolutionary history was inferred using the maximum - likelihood method based on the tamura - nei model with mega6.06 . the tree is drawn to scale , with branch lengths measured in the number of substitutions per site . genbank accession numbers used in this tree are kp985768 , jx458855.1 , fj750957.1 , jx458852.1 , jx458854.1 , fj750958.1 , jx458856.1 , jx458828.1 , jx458826.1 , jx458834.1 , dq447651.1 , jx458846.1 , ay358025.2 , dq447657.1 , z12132.1 , nc_001608.3 , z29337.1 , ef446132.1 , jn408064.1 , kc545388.1 , kc545387.1 , dq447649.1 , ef446131.1 , dq447652.1 , fj750956.1 , fj750955.1 , and fj750953.1 . we do not know why the patient did not transmit marv to any of his close contacts . we can assume that none of the contacts had substantial exposure to the patient while he was infectious . the relatively small size of this and previous filovirus outbreaks in uganda can be attributed to enhanced vhf surveillance , rapid case identification , laboratory testing , and investments from the global health security agenda in rapid sample transportation to the national vhf reference laboratory for diagnostic testing ( 13 ) . vhf surveillance continues to be a top priority for uganda , and the vhf surveillance program continues to play a crucial role in detecting , responding to , and helping to control these outbreaks .