2002/106/EC: Commission Decision of 1 February 2002 approving a Diagnostic Manual establishing diagnostic procedures, sampling methods and criteria for evaluation of the laboratory tests for the confirmation of classical swine fever (Text with EEA relevance) (notified under document number C(2002) 381) (c. 106)

ANNEX U.K. CLASSICAL SWINE FEVER DIAGNOSTIC MANUAL

F1 F2 F3 F4 F5 F6 CHAPTER VII U.K. Principles and use of serological tests and evaluation of their results

A. Basic principles and diagnostic value U.K.

1. In classical swine fever virus infected pigs, antibodies are usually detectable in serum samples from two to three weeks after infection. In pigs that have recovered from the disease, protective neutralising antibodies can be detected for several years or even for their lifetime. Antibodies are also sporadically detectable in the terminal stage of lethally diseased animals. In some pigs with chronic form of classical swine fever, antibodies might be detectable for a few days at the end of the first month post-infection. U.K.

Pigs infected in utero may be immunotolerant against the homologue classical swine fever virus and produce no specific antibodies. However, antibodies of maternal origin can be detected during the first days of life. The half-life of maternal antibodies in non-viraemic healthy piglets is about two weeks. If found in piglets older than three months, classical swine fever antibodies are very unlikely to be of maternal origin.

2. The detection of antibodies against classical swine fever virus in serum or plasma samples is carried out to assist the diagnosis of classical swine fever in suspected holdings, for establishing the age of infection in case of a confirmed outbreak and for monitoring and surveillance purposes. However, serological tests are of limited value for the detection of classical swine fever in the case of a recent infection in a holding. U.K.

A few seropositive pigs with a low neutralisation titre can be indicative of a recent infection (two to four weeks). Many pigs with high neutralisation titre could indicate that virus entered the holding more than one month before. The location of seropositive pigs in the holding can provide valuable information on how classical swine fever virus entered the holding.

However, an accurate evaluation of the results of the serological tests must be carried out taking into account the whole clinical, virological and epidemiological findings, in the framework of the enquiry to be carried out in case of suspicion or confirmation of classical swine fever, in accordance with Article 8 of Directive 2001/89/EC.

Textual Amendments

F1 Word in Annex Ch. 7 Section B para. 1 substituted (31.12.2020) by The Exotic Disease (Amendment etc.) (EU Exit) Regulations 2018 (S.I. 2018/1410), regs. 1, 7(8)(a)(i); 2020 c. 1, Sch. 5 para. 1(1)

F2 Words in Annex Ch. 7 Section B para, 1 omitted (31.12.2020) by virtue of The Exotic Disease (Amendment etc.) (EU Exit) Regulations 2018 (S.I. 2018/1410), regs. 1, 7(8)(a)(ii); 2020 c. 1, Sch. 5 para. 1(1)

F3 Word in Annex Ch. 7 Section B para. 4 substituted (31.12.2020) by The Exotic Disease (Amendment etc.) (EU Exit) Regulations 2018 (S.I. 2018/1410), regs. 1, 7(8)(b); 2020 c. 1, Sch. 5 para. 1(1)

F4 Word in Annex Ch. 7 Section B para. 6 substituted (31.12.2020) by The Exotic Disease (Amendment etc.) (EU Exit) Regulations 2018 (S.I. 2018/1410), regs. 1, 7(8)(c)(i); 2020 c. 1, Sch. 5 para. 1(1)

F5 Words in Annex Ch. 7 Section B para. 6 substituted (31.12.2020) by The Exotic Disease (Amendment etc.) (EU Exit) Regulations 2018 (S.I. 2018/1410), regs. 1, 7(8)(c)(ii); 2020 c. 1, Sch. 5 para. 1(1)

F6 Words in Annex Ch. 7 Section B para. 6 omitted (31.12.2020) by virtue of The Exotic Disease (Amendment etc.) (EU Exit) Regulations 2018 (S.I. 2018/1410), regs. 1, 7(8)(c)(iii); 2020 c. 1, Sch. 5 para. 1(1)