van Oirschot J T
Virus Discovery Unit, ID-Lelystad, PO Box 65, 8200 AB, Lelystad, The Netherlands.
Vet Microbiol. 2003 Nov 7;96(4):367-84. doi: 10.1016/j.vetmic.2003.09.008.
There are two types of classical swine fever vaccines available: the classical live and the recently developed E2 subunit vaccines. The live Chinese strain vaccine is the most widely used. After a single vaccination, it confers solid immunity within a few days that appears to persist lifelong. The E2 subunit vaccine induces immunity from approximately 10-14 days after a single vaccination. The immunity may persist for more than a year, but is then not complete. The Chinese strain vaccine may establish a strong herd immunity 1-2 weeks earlier than the E2 vaccine. The ability of the Chinese vaccine strain to prevent congenital infection has not been reported, but the E2 subunit vaccine does not induce complete protection against congenital infection. Immunological mechanisms that underlie the protective immunity are still to be elucidated. Both types of vaccine are considered to be safe. A great advantage of the E2 subunit vaccine is that it allows differentiation of infected pigs from vaccinated pigs and is referred to as a DIVA vaccine. However, the companion diagnostic E(rns) ELISA to actually make that differentiation should be improved. Many approaches to develop novel vaccines have been described, but none of these is likely to result in a new DIVA vaccine reaching the market in the next 5-10 years. Countries where classical swine fever is endemic can best control the infection by systematic vaccination campaigns, accompanied by the normal diagnostic procedures and control measures. Oral vaccination of wild boar may contribute to lowering the incidence of classical swine fever, and consequently diminishing the threat of virus introduction into domestic pigs. Free countries should not vaccinate and should be highly alert to rapidly diagnose any new outbreak. Once a new introduction of classical swine fever virus in dense pig areas has been confirmed, an emergency vaccination programme should be immediately instituted, for maximum benefit. The question is whether the time is ripe to seriously consider global eradication of classical swine fever virus.
经典活疫苗和最近研发的E2亚单位疫苗。中国活疫苗株是使用最广泛的。单次接种后，它能在几天内产生牢固的免疫力，且这种免疫力似乎能持续终身。E2亚单位疫苗在单次接种后约10 - 14天诱导产生免疫力。这种免疫力可能持续一年以上，但随后并不完全。中国疫苗株可能比E2疫苗提前1 - 2周建立强大的群体免疫力。中国疫苗株预防先天性感染的能力尚未见报道，但E2亚单位疫苗不能诱导完全预防先天性感染。保护性免疫的免疫机制仍有待阐明。两种疫苗都被认为是安全的。E2亚单位疫苗的一个巨大优势是它能区分感染猪和接种猪，被称为鉴别诊断疫苗（DIVA疫苗）。然而，用于实际进行这种区分的配套诊断E(rns) ELISA仍需改进。已经描述了许多研发新型疫苗的方法，但在未来5 - 10年内，这些方法都不太可能使一种新的DIVA疫苗上市。在经典猪瘟流行的国家，通过系统的疫苗接种运动，辅以常规诊断程序和控制措施，能最好地控制感染。对野猪进行口服疫苗接种可能有助于降低经典猪瘟的发病率，从而减少病毒传入家猪的威胁。无疫国家不应进行疫苗接种，应高度警惕迅速诊断任何新的疫情爆发。一旦在密集养猪地区确认新引入经典猪瘟病毒，应立即启动紧急疫苗接种计划，以获取最大效益。问题是现在是否已到认真考虑全球根除经典猪瘟病毒的时机。
