目前一种在亚洲推广的五价疫苗的安全性受到广泛质疑。这种疫苗被设计成预防白喉、百日咳、破伤风、乙肝以及B型流感嗜血杆菌五种疾病和细菌。然而近几周来由于不断出现的安全事故，其安全性受到各方的质疑。目前斯里兰卡、不丹和越南已经临时停止了这种疫苗的应用。而印度则启动了对该疫苗的安全调查。虽然WHO组织声称该疫苗是安全有效的，但是在印度自从2011年开始推广这种疫苗后已经有21名婴儿接种后死去。

　　印度使用的疫苗来自于本土的Biological E and Serum Institute 以及强生和葛兰素史克等跨国药企。一位WHO官员表示，婴儿死亡与接种疫苗之间很难确定有直接的因果关系。目前调查仍在进行当中。

　　详细英文报道：

　　Intense scrutiny has accompanied the introduction of pentavalent vaccines throughout Asia. Sri Lanka, Bhutan and Vietnam temporarily suspended their use following adverse events. Now India is running a study to assess the safety of the vaccine.

　　India has administered pentavalent vaccines to protect against diphtheria, pertussis, tetanus, hepatitis B and haemophilus influenza type B since 2011, but criticisms of the jab have intensified in recent weeks. Last month The Indian Journal of Medical Ethics criticized the World Health Organization (WHO) for continuing to promote the vaccine despite reports of serious adverse events occurring following immunization. The WHO maintains the vaccine is safe, effective and provides tremendous public health benefits.

　　However, with 21 infant deaths occurring following immunization, India is to run its own tests with support from the WHO. "A major study is to be launched soon on the safety and effectiveness of pentavalent vaccine and to go into background of these deaths," chairman of the Committee of the Ministry of Health and Family Welfare N.K. Arora told the Economic Times. Pentavalent jabs from Indian manufacturers Biological E and Serum Institute of India are prequalified by WHO. Johnson & Johnson ($JNJ) subsidiary Crucell, GlaxoSmithKline ($GSK) and LG Life Sciences also have pentavalent vaccines prequalified by the WHO.

　　A WHO committee reviewed the use of the vaccine in four Asian countries--including India--at a meeting in June. Each country reported serious adverse events following immunization, but health officials were unable to establish a causal relationship between fatalities and the vaccine. "As peak incidence of [sudden infant death syndrome] occurs in early infancy, a close temporal relationship between SIDS and receipt of pentavalent vaccine is expected by simple chance," the committee concluded.