Tecle T, Mickiené A, Johansson B, Lindquist L, Orvell C
Department of Clinical Virology, Huddinge University Hospital, Karolinska Institute, Stockholm, Sweden.
Arch Virol. 2002;147(2):243-53. doi: 10.1007/s705-002-8317-y.
An epidemic of mumps in Lithuania started in December 1998 and continued until May 2000. The total registered number of cases was about 11.000 of a total of 3,7 million inhabitants in Lithuania (29,7 cases/10,000). Virus-containing samples were collected from 80 patients treated at the hospital of Kaunas from October 1999 until the end of the epidemic. Out of the 80 patients with parotitis, meningitis was observed in 11 patients and orchitis in 22 of 69 male patients. Twenty-seven virus strains were genotyped by nucleotide sequencing of the small hydrophobic (SH) protein gene, and the 57 amino acid sequences of the gene were deduced. Twenty-five virus strains belonged to the C genotype and two were of the D genotype. By phylogenetic analysis the virus strains causing meningitis grouped in a separate cluster, designated C1, within the C genotype. Another group of ten of the 25 genotype C strains exhibited an amino acid triplet at amino acid positions 28 to 30 of the protein, consisting of valine, alanine and serine, instead of the previously recognised valine, valine and serine combination of genotype C. The amino acid alanine at position 29 was found in combination with the amino acid serine at position 48. This variant was designated C2 and it was associated with parotitis. The amino acid alanine at position 29 and serine in position 48 of the C2 genotype may constitute a marker of low neurovirulence compared to other genotype C strains.
立陶宛的腮腺炎疫情始于1998年12月，一直持续到2000年5月。立陶宛总人口为370万，登记的病例总数约为11000例（29.7例/10000人）。1999年10月至疫情结束期间，从考纳斯医院接受治疗的80名患者中采集了含病毒样本。在80例腮腺炎患者中，11例出现脑膜炎，69例男性患者中有22例出现睾丸炎。通过对小疏水（SH）蛋白基因进行核苷酸测序，对27株病毒进行了基因分型，并推导了该基因的57个氨基酸序列。25株病毒属于C基因型，2株属于D基因型。通过系统发育分析，导致脑膜炎的病毒株在C基因型内聚为一个单独的簇，命名为C1。25株C基因型病毒中的另一组在该蛋白的第28至30位氨基酸处出现一个氨基酸三联体，由缬氨酸、丙氨酸和丝氨酸组成，而不是之前公认的C基因型缬氨酸、缬氨酸和丝氨酸组合。在第29位发现的丙氨酸与第48位的丝氨酸同时出现。该变体被命名为C2，与腮腺炎相关。与其他C基因型毒株相比，C2基因型第29位的丙氨酸和第48位的丝氨酸可能构成低神经毒力的标志物。
