Characterization of large mumps outbreak among vaccinated Palestinian refugees.
During a large mumps virus (MuV) outbreak which occurred in the Palestinian refugee camps of the West Bank, 68.1% (2,636/3,871) of the cases were vaccinated with one dose of trivalent measles, mumps, and rubella (MMR) vaccine. Attack rates by camp ranged from less than 1 case per 1,000 people in the population to 43/1,000 (overall, 11/1,000). The outbreak lasted from December 2003 to June 2005, with two peaks, one from April to May 2004 and the other from March to April 2005. To control the outbreak, a mass MMR vaccination campaign was conducted in May 2005. Evaluation of the immune status of cases (n=59) and healthy controls (n=51) revealed high levels of mumps immunoglobulin G (IgG) and a low MuV-specific IgM in clinical cases indicative of a booster immune response. This suggested a secondary rather than a primary infection due to the insufficient protection conferred by the single vaccine dose included in the vaccination program. This prediction was further confirmed by the low seroprevalence (68.6%) found in the healthy control group, which was below the threshold level required for MuV herd immunity. Mumps diagnosis was established mainly by reverse transcription-PCR in clinical samples obtained within 48 h from the onset of disease. Of the parotid fluids and nasopharyngeal aspirates analyzed, 92% were positive for MuV RNA, while only 33% of the urine samples were positive. Phylogenetic analysis of the MuV SH gene identified the outbreak strain as the H genotype, which has been in circulation worldwide at least since 1989.
Hindiyeh
Musa Y
MY
Central Virology Laboratory, Public Health Services, Ministry of Health, Chaim Sheba Medical Center, Tel-Hashomer, Israel. hindiyeh@yahoo.com
Aboudy
Yair
Y
Wohoush
Mahmoud
M
Shulman
Lester M
LM
Ram
Daniela
D
Levin
Tal
T
Frank
Tamar
T
Riccardo
Flavia
F
Khalili
Mohamad
M
Sawalha
Elias-Shlash
ES
Obeidi
Maysoun
M
Sabatinelli
Guido
G
Grossman
Zehava
Z
Mendelson
Ella
E
D000293:Adolescent; D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood; D018912:Arabs; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D005260:Female; D005838:Genotype; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007223:Infant; D008297:Male; D022542:Measles-Mumps-Rubella Vaccine / Q000008:administration & dosage* / Q000276:immunology*; D008875:Middle Aged; D008877:Middle East / Q000453:epidemiology; D008969:Molecular Sequence Data; D009107:Mumps / Q000453:epidemiology*; D009109:Mumps virus / Q000235:genetics* / Q000302:isolation & purification*; D009305:Nasopharynx / Q000821:virology; D010306:Parotid Gland / Q000821:virology; D010802:Phylogeny; D012036:Refugees; D017422:Sequence Analysis, DNA; D014556:Urine / Q000821:virology; D055815:Young Adult
D000914:Antibodies, Viral; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D022542:Measles-Mumps-Rubella Vaccine