# Leptospirosis - Chronological list of serogroups

Icterohaemorrhagiae serogroup - 1915

In the serovar list of 1967 (WHO, 1967) the Icterohaemorrhagiae serogroup consisted of 13 serovars, including sarmin and weaveri, both of which are now considered to be members of the reestablished Sarmin serogroup (see paragraph 3.1.1) and budapest, which recently was withdrawn from the list.

In the said list serovar budapest was given provisional status pending further investigation. Its separate serological status described by Fzy and Csoka (1962) and studied by Babudieri (1966) was not confirmed by any other RL. However, Kmety (1974) reported that serovar budapest was serologically identical to mankarso. At the TSC meeting in Manchester (1986) Terpstra presented the results of his investigations which indicated tht by using monoclonal antibodies, the strain representing serovar budapest behaves as a strain of serovar copenhageni. These conflicting results could be caused by a possible mixed culture with varying proportions of each of the components.

Serovar budapest has therefore been omitted from the REvised List (Kmety, Dikken, 1988).

Serovar icterohaemorrhagiae can be represented by either of the two original published strains viz: Ictero NO. 1 (Inada and Ido, 1915 a and b) or RGA (Uhlenhuth and Fromme, 1916).

As the authenticity of the strain Incero No. 1 was under discussion for many years, the TSC selected RGA as reference strain (Minutes TSC meetings 1966 and 1986). However, after the publication of the detailed description on the history of strain Incero No. 1 by Yamamoto and Yanagawa (1990), tghe TSC decided during its meeting in Osaka (1990), to recognize the authenticity of this strain. Since it had been isolated earlier than RGA, the TSC decided to replace RGA by Ictero No. 1 as reference strain, notwithstanding its serological difference from RGA caused by an additional thermolabile antigen in strain Ictero No. 1 (Borg-Petersen, 1972 and Kmety, 1972).

Because of their serological differences both strains, RGA as well as Ictero No. 1, are included in this paper and in the attached serovar list. Comparative typing studies performed only with strain Ictero No. 1 may lead to confusing typing results.

Two new serovars have been included in the Icterohaemorrhagiae group, viz. tonkini and gem. Another strain, LT 60-69, has now been also confirmed as a new serovar named bogvere, but since its valid description has not yet been published it is listed in the Annex. A Chinese strain Lai placed in the Annex of the Revised List of Serovars (Kmety, Dikken, 1988) and two Korean strains have recently been found to be validly published and are therefore included in the attached updated list as serovar lai, hongchon and yeonchon. As a result of these findings the serogroup consists of 15 serovars.

Hebdomadis serogroup - 1918

During the TSC meeting in Boston in 1982 (Minutes 1984) it was agreed that the large Hebdomadis serogroup should be divided into 3 separate groups, viz. Hebdomadis, Sejroe, and Mini. The new Heb domadis group now contains 12 serovars, including three new ones goiano, sanmartini and manzhuang. After the lit of 1988 was published, serovar manzhuang was described, anbd has now been added to the attached updated serovar list.

On the basis of the results of factor analysis two sub-serogroups (subgroups) were suggested (Dikken and Kmety, 1978) viz. subgroup Nebdomadis containing serovars hebdomadis, kambale, nona and maru and subgroup Borincana with serovars borincana, worsfoldi, jules, kabura, kremastos and goiano. The serovars sammartini and manzhuang have not yet been studied by factor analysis.

Autumnalis seerogroup - 1923

It was decided at the TSC meeting in Boston in 1982 (Minutes 1984) to divide this group into 3 separate groups; Autumnalis, Djasiman, and Louisana.

In the new Autumnalis group the serovar sumatrana was omitted as it was serologically indistinguishable from bulgarica. Serovar butembo has been transferred provisionally from the Cynopteri serogroup to he Autumnalis group as its relationship with serovars within this group appears stronger. If in teh future new strains ar eisolated with serological affinity to butembo, it is possible that they may be considered as considered as constituting a sepearate serogroup. In the REvised List of 1988 the serogroup Autumnalis was extended by the addition of the following serovars: alice, mujunkumi, weerasinge, carlos, srebarna, lambwe, and bim. The Chience serovar nanla, only recently published, is added to the enclosed updated list. However, the serovar status of nanla has not yet been confimed by a RL.

By rechecking the original literature dealaing with serovars alice aynd weerasinghe it was discovered, after the list of 1988 was published, that no descriptions had been given for either serovars. They will therefore have to be removed from the main list and placed within the Annex.

Moreover discrepant typing results have also been reported for serovar alice. With these omissions and the addition of nanla the group now contains 14 serovars.

Pyrogenes serogroup - 1923

The group was originally designated Australis B by Alston and Broom (1958). In the WHO list of 1959 the name was chaned to Pyrogenes. Since the publication of the WHO list of 1967 the group has been extended by the official recognition of the following serovars: camlo, guaratuba, princestown, kwale, and varela. However, because of some typing discrpancies that have recently come to light serovar camlo has now been included only tentatively (marked ++) in the attached updated list of serovars. Two new serovars, menglian and nigeria, represented by strain S 621 and strain Vom respectively were described after the publication of the 1988 list and they have nowbeen included in the attached updated list of serovars.

Bataviae serogroup - 1926

Since 1967 the Bataviae serogroup has been extended by only one serovar, rioja. During the TSC meeting in Boston (1982), strian Swart was accepted as the new reference strain of serovar bataviae in place of strain van Tienen. Also the designations of some of the reference strains, given in the WHO list of 1967, were changed to conform to the reference publications; thus the reference strain for serovar kobbe became CZ 320, for brasiliensis An 776, for balbao 735 U and for claytoni 1348 U.

Strain LT 21-74 that has been redognized by reference laboratiories after the Manchester meeting (1986) as representing a new serovar, provisionally named santarosa, has not yet been published. It has therefore been placed in th Annex of the Revised list of 1988 and in the Annex of the attached updated list.

Also another not published serovar losbanos, with reference strain LT 101-69, is placed in the Annex, although some discrepant typing results have been reported.

Grippotyphosa serogroup - 1928

In the list of 1967 the Grippotyphosa serogroup consisted of only two serovars, grippotyphosa and valbuzzi. Since then it was agreed to transfer canalzonae from the Cynopteri serogroup into the Grippotyphosa group and to further extend the group by four new serovars, vanderhoedeni, ratnapura, muelleri and huanuco. It had been suggested that huanuco should form a separate serogroupo, but since it would have been the only member of that group it was decided to place it provisionally in the Grippotyphosa group as it shows some relationship with members of that group.

Canicola serogroup - 1933

The Canicola group now contains two more serovars than it did in the 1967 WHO list, viz.: partlandvere and kuwait. In the Annex 2 of that list the serovar name attached to teh strain LT 1014 was given as azuli, but that name was never validly published. When published in 1969 by Tedesco et al. the serovar was name galtoni, and this name has been accepted in place of azuli.

On the basis of factor analysis is has been suggested that the roup should be divided into two subgroups viz: Canicola and Schufneri (Dikken and Kmety, 1978).

Australis serogroup - 1937

Since the list of 1967 was compiled the group has first been extended by four serovars: hawain, soteropolitana, ramisi, and the incompletely described Chinese serovar rushan. Serovar nicaragua was included in the WHO serovar list of 1967 under the laboratory code LT 990 on a provisional basis as no publication was known. The strain was subsequently submitted to factor analysis, which confirmed its serological status (Dikken and Kmety, 1978). In 1982 Sulzer described the serovar under the strain designation 1011, which consequently replaces the previous laboratory code.

Serovar pina, strain LT 932 which is included in the WHO list of 1967 with a footnote, "provisonal classification, pending futher work" has not been included in teh present list as it has not yet been published. Since the strain was typed by Galton who considered that it represented a separate serovar it has been placed in the Annex to the new serovar list (1988).

Further investigations have shown that serovar bangkok is indistingushable from serovar australis (Kmety and Terpstra, personal communications) and it has therefore been omitted from the Revised List of 1988.

Latel serovarbajan has been described. The serogroup now constains 13 serovars.

Pomona serogroup - 1937

In the WHO list of 1967 the serogroup contained 6 serovars of which two, monjakov and kennewicki have been shown by agglutiinin-absorption and y monoclonal anitbody test to belong to serovar pomona. They have therefore been excluded from the Revised List. The group now includes serovar tsarastovo, although some discrepant typing results were reported by Hathaway et al.(1985). It also includes a Chinese serovar kunming in spite of a lack of data on its history.

Javanica serogroup - 1938

Since the publication of the WHO of 1967, eight new serovars have been added to the Javanica serogroup which now contains a total of 14 serovars. Six of them were already officially recognized by the TSC Manchester, 1986, and they are included in the Revised List of 1988, viz.: serovars menoni, fluminense, and four Chinese serovar A 85, dhong, menrun and yaan. Two additional Chincese serovars, mengma yand zhenkang were only published recently and the therefore included in the attached updated serovar list.

The serovar status of there new serovars fluminense, mengma and zhenkan are still under investigation, and the other four new Chinese strains have incomplete documentation (i.d.). The serovar disignation A 85 does not agree with the requirements of the IC and will have to be changed. (Probably to mengla, personal communications).

One other serovar, referred to as vargonicas, reference strain 24, although confirmed by RLs, has not yet been validly published and has therefore been placed in the Annex to the Revised List of 1988.

In the list of 1967. Annex 2, serovar ceylonica was included while still unpublished, with the reference strain iven as Dyananda. When published by Nityananda et al. (1969) the strain name was given as Piyasena. This name has therefore been given to the reference strain on the Revised (1988) and attached lists.

Sejroe serogroup - 1938

The Sejroe group is now formed from about haflt the number of serovars contained in the previous enlarged Hebdomadis group. It now contains 19 serovars.

Serovar nero, having been found to be indistinguishable from saxkoebing, is no longer included. Serovars gorgas with strain LT 829, recreo with strain LT 957, and trinidad with strain LT 1098 were included in the 1967 Annex 2 list, but were unpublished at that time. When the publication appeared (Sulzer et al., 1982), they were given different reference strain designations 1413 U, 380 and TRVL 34056 respectively. As proposed by Dikken and Kmety (1987) these designations were accepted by the TSC (Manchester, 1986) and they replaced the original designations.

According to the results of factor analysis (Kmety, 1977) the Sejroe serogroup can be divided into 3 subroups:

- Sejroe with serovars sejroe, polonica, balcanica and the additional seovar istrica;

- Saxkoebing with serovars saxkoebing, haemolytica, ricardi, and two additional serovars nyanza and dikkeni;

- Wolffi with serovars medanensis, wolffi, hardjo, gorgas, recreo, trinidad, and 4 additonal serovars roumanica, caribe, geyaweera and guaricura.

Cynopteri serogroup - 1939

This small group was reduced to one serovar when candzonae was transferred to the Grippotyphosa serogroup and serovar butembo to the Autumnalis group. However, a new serovar named tingomaria has now been added.

Djasiman serogroup - 1939

The Djasman group was established at the TSC meeting in Boston in 1982 (Minutes, 1984) with three serovars from the Autumnalis group, djasiman, sentot and guringi. Recently the group was extended by the addition of two new serovars huallaga and agogo.

Serovar huallaga was added to this group in the Revised List of 1988.

Authough confirmed by a RL, serovar agogo was not published at the time of the TSC meeting in Manchester (1986), and has therefore been placed in the Annex of the Revised List of 1988.

Having been published (Hogerzeil et al., 1986) soon after the Manchester meeting the serovar is now removed from the Annex and placed in the attached updated main list.

Sarmin serogroup - 1939

Serovar sarmin appeared in the first serovar list of 1954 (Wolf and Broom) when it represented a separate serogroup. Being the only member of the group it was tentatively transferred to the Icterohaemorrhagiae serogroup in the list of 1967.

After the valid descriptions of the serovars weaveri, waskurin, rio and machiguenga, which are related to sarmin, the Sarmin serogroup was reestblished (TSC, Manchester, 1986). Recently serovar cuica was described (Pereira et al., 1991). The serogroup now contains 6 serovars.

Mini serogroup -1941

The Mini group, the third group to be separated from the previous Hebdomadis serogroup has been enlarged to 9 serovars by the addition of serovars ruparupae, hekau and yunnan. Serovarruparupae was already included in the Revised List of 1988. The Chincese serovars hekau and yunnan are recently published and therefore only now included in the attached updated list of serovars. Their serovar status has yet to be confirmed by a RL and they are therefore given provisional status (+).

In the 1967 list of serovars beye and tabaquite were included with unpublished references, under the strain numbers LT 844 and TVRL 34056 respectively. These have now been changed to 173U and TVRL 3214 according to the designations given in the original publication of Sulzer et al. (1982).

Tarassovi serogroup - 1941

The Tarassovi group which, in the 19067 list consisted of 10 serovars, has grown consierably and now comprises 21 serovars.

In the last approved list of serovars of 1988, the group extended by 7 serovars: tunis, kaup, vughia, navet, kanana, darien and mogdeni.

Since then 4 new Chinese serovars banna, gengma, mengpeng and yunxian have been described within this serogroup. These serovars have notyet been confirmed by a RL and they are therefore listed under provisional status (+) in the attached updated list.

Serovars charges and gatuni, included in the 1967 listwere unpublished at that time and their reference strains were quoted as LT 924 and LT 839 respectively. These have now been changed to 1913 K and 1473 K according to the designations given in the original publication of Sulzer et al. (1982).

Two further strains M 39090 and LT 82 have been studied by RLs and found to represent new serovars. The serovar names that have been suggested are langati and sulzerae. As they have not yet been published they are included in the Revised (1988) and attached serovar lists.

Ballum serogroup - 1944

The Ballum group was extended by the addition of serovars kenya and ballum 3. It had been suggested that serovar kenya, strain Njenga should form a separate serogroup. However, as it would have been the sole member of that group the TSC at its Manchester meeting of 1986 decided to include the serovar provisionally in serogroup Ballum to which it is serologically related.

Serovar ballum 3 was included although it is recognized that the name does not conforms to the IC and will have to be changed.

Celledoni serogroup - 196

The original group has been enlarged by the addition of serovar anhoa and two Chinese serovaars, publiched as javanica 4 and hainan - whitcombi. Because the last two names do not conform to the requirements of the IC, it has been suggested by personal correspondence with the authors that the names should be changed to mangdeng and hainan. As those names have not yet been published, they could not be included in the Revised (1988) and attached list.

Lousiana serogroup - 1964

This group was formed by the separation from the previously large Autumnalis serogroup of the two serovars louisana and orleans. It was extended by the addition of the serovar lanka.

Panama serogroup - 1966

In the 1967 list this group consisted of two serovars, panama and cristobali. Although still unpublished at that tiem cristobali was included with its reference strain LT 940. In the original publication (Sulzer, 1982) the reference strain is designated 1996 K, which now replaces the former on in the Revised (1988) and attached lists. The group has been further extended by the addition of serovar mangus, reference strain TRVL/CAREC 137774, with provisional status (+).

Ranarum serogroup - 1972

This new serogroup was established at the TSC meeting in Manchester in 1986, based on the biological properties and the serological relationship of the serovars compasing the group.

The group consists of serovars ranarum, evansi and pingchang. Literature on pingchang became available only after the list of 1988 was published. The serovar is now included in this serogroup in the attached updated list of serovars. Its serovar status has been confirmed by a RL.

Manhao serogroup - 1978

The establishment of a new serogroup Manhao was proposed in 1979 in a publication of the Chinese Military Institute, the Department of Logistics oftghe KunmingMilitary Area and the National Institute for the Control of Pharmaceutical and Biological Products, Beijing, China (individual authors not mentioned). This proposal was accepted by the TSC meeting in Manchester, 1986. The proposal was based on the results of a serological study of four strains designated as serovars manhao 1,2,3 and 4. Serovar manhao 4 and its reference strain Li 130 was apparently described by Luo Heng-sheng et al. in 1978. In a paper by Gao Ji-yuan et al.(1984) designations for the reference strains attached to serovars manhao 1, 2 and 3 are given as L70, L105 and L60 respectively.

The Manhao serogroup was futther extended by the addition of serovar lincang with its reference strain, L14 which described Qin Jin-cai et al. in 1981.

These Chinese strains were investigated by Terpstra and his co-workers in Amsterdam. It was found that mahnao 1,2 and 3 were so closely related that they could be considered as belonging to the same serovar. In agreement with the Chinese workers serovar manhao 2 was choosen as the representative serovar with reference strain L 105.

The group now consists of the serovars manhao 4 and 3, both marked by i.d. because of incomplete documentation and serovar lincang marked by ++ because of controversal typing results.

Shermani serogroup - 1982

In the serovar list of 1967 this group consisted of only one serovar shermani with LT 821 as its reference strain, based on an unpublished reference. The relevant publication (Sulzer, 1982) refers to the strin as 1342 K, which replaces the previous desination in the Revised List of 1988. The group was extended by the addition of serovar luis that was thought at first to be a member of the Tarassovi serogroup. Further investigations however showed that strain M 6 of luis was serologically more closely related to chermani and consequently the TSC at therir Manchester meeting in 1986 decided that it should be placed within the Chermani serogroup.

Three other strians, MW 4, CI 40, and 9160 were shown to represent three new serovars within the Shermani serogroup. Although their descriptions have not yet ben published, they are listed in the Annex to the Revised (1988) - and attached list under the proposed serovar names, aguaruna, babudieri and carimagua respectively.