Khan E, Hasan R, Mehraj V, Nasir A, Siddiqui J, Hewson R
Department of Pathology & Microbiology, The Aga Khan University Hospital, Stadium Road, P.O. Box 3500, Karachi 74800, Pakistan.
J Clin Virol. 2008 Oct;43(2):176-9. doi: 10.1016/j.jcv.2008.06.003. Epub 2008 Jul 18.
The status of dengue genotypes involved in the recent epidemic out-breaks in Pakistan is not well defined.
We sought to analyze the predominant genotype responsible for the most severe and largest out-break of dengue hemorrhagic fever (DHF) that hit Karachi in 2006.
Retrospective analysis of stored serum samples for dengue virus genotype by multiplex RT-PCR, anti-dengue IgM, IgG and review of clinical charts of patients admitted to Aga Khan University Hospital.
Viral RNA detection of 250 patients revealed positive results in 185 (74.0%) samples. DEN-2 was predominant genotype (n=104, 56.2%) Dengue specific antibodies were detected in 139 samples of which 81 were classified as primary cases. DEN-2 accounted for these. Within secondary cases, 63.2% were due to DEN-2 (total 57), the rest were positive for DEN-3. DHF (p=0.064) and abdominal pain (p=0.059) were more frequently associated with DEN-2 as compared to DEN-3. None of the samples were positive for DEN-1 or DEN-4.
Co-circulation of DEN-2 and DEN-3 was responsible for the 2006 out-break in Karachi. Primary and secondary cases were seen in both groups. Cases with DHF showed marginal association with DEN-2. Introduction of a new serotype (DEN-3) and or a genotypic shift of endemic serotype (DEN-2) are the probable factors for the recent out-break of DHF in this region.
巴基斯坦近期登革热疫情中涉及的登革热基因型状况尚不明确。
我们试图分析导致2006年袭击卡拉奇的最严重、规模最大的登革出血热（DHF）疫情的主要基因型。
采用多重逆转录聚合酶链反应（multiplex RT-PCR）对储存的血清样本进行登革热病毒基因型回顾性分析，检测抗登革热IgM、IgG，并查阅阿迦汗大学医院收治患者的临床病历。
对250例患者的病毒RNA检测显示，185份样本（74.0%）呈阳性结果。DEN-2是主要基因型（n = 104，56.2%）。在139份样本中检测到登革热特异性抗体，其中81份被归类为原发性病例，均由DEN-2引起。在继发性病例中，63.2%由DEN-2引起（共57例），其余为DEN-3阳性。与DEN-3相比，DHF（p = 0.064）和腹痛（p = 0.059）与DEN-2的关联更为频繁。没有样本DEN-1或DEN-4呈阳性。
DEN-2和DEN-3的共同流行导致了2006年卡拉奇的疫情。两组均出现了原发性和继发性病例。DHF病例与DEN-2的关联不明显。引入新血清型（DEN-3）和/或地方性血清型（DEN-2）的基因型转变可能是该地区近期DHF疫情爆发的因素。
