Rotavirus-specific breast milk antibody in two populations and possible correlates of interference with rhesus rotavirus vaccine seroconversion.

Milk was collected from 56 New York and 70 Venezuelan mothers participating in Rhesus rotavirus (RRV) pediatric vaccine trials. Plaque reduction neutralization antibody (PRNA) to RRV (VP7:3, VP4:RRV) and human P rotavirus (VP7:3, VP4:P) and epitope-blocking antibody to one RRV VP4 and VP7 epitope were determined. Controlling for postpartum age, more Venezuelan milk samples had detectable RRV and P PRNA, RRV VP4 epitope-blocking antibody (P less than or equal to .001), and higher RRV and P PRNA geometric mean titers (P = .01) than New York samples. Using a logistic regression model, both milk and infants' serum preimmunization RRV PRNA titers had a negative effect on seroconversion (P = .008 and .02, respectively). Only 25% (2/8) infants fed milk containing greater than or equal to 1:160 RRV PRNA seroconverted compared with 83% (5/6) fed milk containing less than 1:160 RRV PRNA (P = .1). Of milk samples containing greater than or equal to 1:160 RRV PRNA, seven (88%) of eight had greater than fourfold neutralizing activity against RRV versus P (P = .035), suggesting that VP4-specific milk antibodies may interfere with RRV seroconversion.     

乌鲁木齐地区婴幼儿腹泻轮状病毒分子流行病学研究

目的了解乌鲁木齐地区婴幼儿轮状病毒腹泻流行情况。方法收集新疆自治区人民医院2007年1～12月住院和门诊0～60月龄婴幼儿腹泻标本376份,ELISA筛查轮状病毒(RV),用RT-PCR对RV毒株进行基因分型。结果共检测376份标本,轮状病毒阳性181份,阳性率48.14%。感染者主要为出生24个月以内的婴幼儿(占98.34%)。9～10月为RV腹泻流行高峰。对161份阳性标本进行G/P基因分型,G1型是主要优势株,占31.68%,其次为G9型(21.12%)、G3型(15.53%)和G2型(14.91%),混合G型感染占14.29%,4例(2.48%)未能分型;P基因型以P[8]为主,占46.58%,其次为P[6](18.63%)、P混合感染(18.01%)和P[4](14.91%),3例(1.86%)未能分型;常见G/P组合G1P[8](24.84%)。结论轮状病毒是乌鲁木齐地区婴幼儿腹泻的主要病原,2007年G1P[8]是主要流行株,G9型成为本地区的第二大优势株。     

上海地区婴幼儿院内感染轮状病毒致腹泻病的分子流行病学调查

目的 了解上海地区婴幼儿院内感染轮状病毒(RV)致腹泻病的分子流行病学特征.方法 采用胶体金法和套式PCR,对2006年11月至2008年1月复旦大学附属儿科医院收集的226例院内感染性腹泻患儿的粪便标本进行RV病原检测,并对阳性标本进行分型,调查患儿的临床特征.数据分析分别以构成比、阳性榆出率表示,均值采用t检验.结果 胶体会法RV阳性率为47.8%.院内感染RV腹泻以1岁以内的年龄段最高,新生儿占RV腹泻患儿的32.4%.发病高峰在10、11月份.采用套式-PCR对除新生儿外的67份RV阳性标本进行分型,G3为主要流行的血清型,占46.3%,其次为G1占23.9%、G2占3.0%、G9占1.5%,7份为混合感染,均为G1、G3混合,10份未能分型.从P分型来看,主要流行株为P[8]型,占90.0%,其次为P[4]型占6.0%,3份标本未能分型.未发现P[6]、PE9]和P[10]型.G3P[8]为主要分离株,占61.2%,其次为G1P[8],占17.9%,G1、G3P[8]混合感染占9.5%,G2P[4]、G8P[9]各1例.新生儿32份RV阳件标本中10份成功分型,均为G1P[8].院内感染RV腹泻延长住院天数、增加住院费用.结论 RV是上海地区院内感染性腹泻病的主要病原,其流行的主要血清型为G3P[8]型,但仍需加强监测G1流行株的暴发流行.     

Rotavirus-specific cytotoxic T lymphocyte response of mice after oral inoculation with candidate rotavirus vaccine strains RRV or WC3

The immunologic basis of homotypic and heterotypic protection by immunization with two candidate rotavirus vaccine strains (simian strain RRV and bovine strain WC3, respectively) was investigated. Mice were orally inoculated with RRV, and 6 d later splenic lymphocytes lysed target cells infected with RRV (serotype 3) but not with human rotavirus serotypes 1 or 2; 4 w after inoculation, cytotoxic T lymphocytes (CTLs) generated in vitro from CTL precursors were also strain-specific. Also, the frequency of RRV-specific CTLs from CTLp after RRV immunization was 20-fold greater than that of cross-reactive CTLs. Inoculation of mice with WC3 (serotype 6), on the other hand, produced cross-reactive CTLs from CTLp at 4 w; CTLs lysed target cells infected with WC3 or human serotypes 1, 2, or 3 to the same extent. The frequency of cross-reactive CTLs after WC3 immunization was greater than or equal to 20-fold greater than that of WC3-specific CTLs. Cross-reactive, rotavirus-specific CTLs induced after WC3 immunization may in part explain the immunologic basis of protection against heterotypic challenge.     

南京地区2011-2012年度门诊婴幼儿轮状病毒腹泻的分子流行病学研究

目的 了解南京地区门诊婴幼儿轮状病毒腹泻的分子流行病学特征及轮状病毒的G/P分型状况。方法 2011年7月至2012年6月对门诊腹泻患儿标本进行轮状病毒胶体金检测,阳性标本通过巢式反转录聚合酶连反应进行G/P分型,同时测序得出亚型。 结果 在2 081例腹泻标本中共检出胶体金阳性标本165例,阳性率为7.9%。轮状病毒感染的高峰季节在10月到次年2月之间, 94%的感染患儿都在2岁以下,其中13～24月龄为高发年龄段。轮状病毒分型结果表明G1, G3, G9为主要G分型,而P\[8\]则是最常见的P分型。常见的G／P组合为：G1P\[8\](16.4%), G3P\[8\](13.9%), G9P\[8\](24.8%)。进一步VP7和VP4基因测序比对后发现G1和G3毒株各分属于一个亚型G1 Ic,G3 Ia,而G9毒株大部分属于G9 IV亚型,同时也有一小部分毒株属于G9 III亚型,P\[8\]型毒株主要为P\[8\] II亚型,少数为P\[8\] IV亚型。 结论 研究结果表明G9P\[8\]是最主要的流行型别,同时G1P\[8\]和G3P\[8\]也占较大比例。     

Protective effect of WC3 vaccine against rotavirus diarrhea in infants during a predominantly serotype 1 rotavirus season

We used a double-blind, placebo-controlled trial to study the efficacy of WC3 rotavirus vaccine administered to 104 infants (ages, three to 12 months) before the rotavirus season. Forty-nine infants received vaccine; 55 received placebo. Rotavirus disease during this season was predominantly caused by a serotype 1 strain. In placebo recipients there were 14 cases of rotavirus diarrhea (attack rate, 25%); 11 were moderate to severe (attack rate, 20%). Vaccinees experienced only three cases of rotavirus disease (attack rate, 6.1%), all mild. When all cases (whether associated with rotavirus or not) of clinically significant diarrhea (CSD) were evaluated, WC3 vaccine provided statistically significant (P less than .01) protection against the total number of episodes of CSD and reduced the number of days of CSD-associated diarrhea, vomiting, fever, or illness. Seventy-one percent of the WC3-vaccinated infants had serum antibody responses to the vaccine. The 14 placebo recipients who experienced natural disease predominantly had antibody responses to serotype 1. Sera taken after the rotavirus season revealed a nearly identical rate (40%) of natural rotavirus infection in the vaccinated and placebo groups.     

轮状病毒感染性腹泻合并多器官功能损害40例临床分析

目的探讨轮状病毒感染性腹泻合并多器官功能损害的临床表现及诊疗方法。方法选取2010-12～2011-03我院儿科住院的轮状病毒感染性腹泻合并多器官功能损害患儿40例。入院后均采集新鲜大便做轮状病毒抗原检测,并做大便培养,同时检测肝肾功能、心肌酶谱、血电解质、C反应蛋白。结果 40例患儿出现不同程度的呼吸系统症状、肝功能异常、尿常规检查异常、心肌酶异常、电解质和C反应蛋白改变等。结论出现轮状病毒感染性腹泻患儿易并发肠道外脏器功能损害,及时检测并给予早期治疗是防治的关键。     

Prognosis of rotavirus diarrhea

OBJECTIVE: To compare the severity of rotavirus diarrhea (RV) and non-rotavirus diarrhea. MATERIAL AND METHODS: Between October 1994 and March 1995, a cross-sectional study was performed in 520 infants with acute diarrhea, at seven primary care level centers in five states of Mexico. Diagnosis of RV was done through immunoenzymatic assay or electrophoresis. Central tendency measures were used for data analysis. Results were presented as means and standard deviations, or median and variation. RESULTS: RV was isolated from 264 children; most of them were males aged 6 months to 1 year. Differences in clinical manifestations were statistically significant between the rotavirus-positive group and the rotavirus-negative group, in the following variables: median number of stools/24 hours; frequency of vomiting; temperature > 38 degrees C; dehydration; and clinical severity scoring. CONCLUSIONS: These results showed a poorer prognosis and a higher severity of rotavirus diarrhea, as compared to non-rotavirus diarrhea in infants.     

1998深圳市秋冬季婴幼儿轮状病毒的感染状况及分子流行病学调查

轮状病毒在全世界分布广泛,是引起婴幼儿腹泻的重要病原,在腹泻病的病毒病因中,它占整个腹泻病的1/4,无论在发达或发展中国家,A组(婴幼儿)轮状病毒引起的腹泻都有较高的发病率,是婴幼儿发病和致死的重要病因。因此,对婴幼儿腹泻及时明确病因,对治疗、预防和流行病学研究都有重要意义。本文对深圳市1998年53例腹泻婴幼儿类便标本中轮状病毒感染状况进行分析。现报道如下。1　材料与方法1.1　标本收集　1998年10月至次年1月份,在深圳市人民医院采集急性胃肠炎患儿粪便标本53份,保存于-20℃备用。1.2　HRV-RNA提取　基本上按Clarke等〔1〕…     

成人腹泻病人轮状病毒感染监测及分组分型研究

目的研究武汉市成人腹泻病人轮状病毒的感染状况及A组轮状病毒基因型的分布。方法收集2001—2002年度武汉市成人腹泻大便标本728份,用聚丙烯酰胺凝胶电泳进行轮状病毒检测,逆转录—聚合酶链反应进行A组轮状病毒基因型研究。结果和结论2001—2002年度武汉市成人腹泻病人A、B组轮状病毒检出率分别为7.83%和0.27%。A组轮状病毒以G3P[8]型为主。成人A组轮状病毒流行的季节和基因型别与婴幼儿的一致。     

The immune response in primary asymptomatic and symptomatic rotavirus infection in newborn infants

Systemic and mucosal immune responses were determined using an enzyme-linked immunosorbent assay in 18 infants (7-86 days old) experiencing primary rotavirus infections over two winters. Fifteen infected infants were asymptomatic; 3 had diarrhea. Neutralization antibody (NA) was assayed in two asymptomatic infants who had a serotype 1 isolate identified. Seven asymptomatic infants had sera available for analysis; none had IgG, 1 had IgM, but 4 had IgA antibody responses. Neither tested infant had a serotype 1 NA rise. In the 3 symptomatic infants, 1 had IgG, 2 had IgM, and all had IgA serum antibody responses detected. Eleven (73%) of 15 asymptomatic and all symptomatic infants had a rotavirus-specific fecal antibody response. These findings identify IgA as an important antibody in primary rotavirus infection in very young infants. The predominance of this antibody in asymptomatic infants suggests that their responses (and protection on subsequent reexposure) may be primarily mucosal.     

Effect of vaccination on serotype-specific antibody responses in infants administered WC3 bovine rotavirus before or after a natural rotavirus infection

In an evaluation of WC3 bovine rotavirus (serotype 6) vaccine in infants, some subjects experienced a natural serotype 1 rotavirus infection before vaccination and others after. Therefore, the effects of both WC3 and natural rotavirus strains as either primary or boosting immunogens on serotype-specific neutralizing antibody responses could be determined. After primary natural infection (symptomatic or asymptomatic), neutralizing antibody titers were highest to serotype 1 but were consistently high to serotype 3, and low titers (greater than or equal to 20) to serotypes 2 and 4 were often detected. Previous vaccination with WC3 had little effect on the magnitude of these responses. In contrast, subjects infected with serotype 1 strains before vaccination experienced large (average, 12-fold) rises in neutralizing antibody to human serotypes 1-4 when vaccinated with WC3. Thus, although WC3 and the natural strains are distinct serotypes, their epitopes were sufficiently similar that reinfection with WC3 could boost neutralizing antibody titers to human serotypes in subjects primed by a previous natural infection.     

Low antibody response in infants with measles and children with subclinical measles virus infection

During a measles epidemic (December 1979-March 1980) in two adjacent villages in Tamil Nadu, 78 of 143 under-fives were affected, eight of whom died, giving an attack rate of 54% and case-fatality rate of 10%. Seven months later 72 children (41 with measles, seven with history of measles in prior epidemics and 24 with no history of measles) were bled to measure measles virus haemagglutination-inhibition antibody. Of the 48 with measles history, 46 had measurable antibody. Surprisingly, of the 24 without a history, 16 had measurable antibody indicating the frequency of subclinical measles during epidemics. The geometric mean antibody titre was lower in infants with measles than in older children (P less than 0.05). The mean titre was lower in those with subclinical measles than in those with clinical measles (P less than 0.01).     

Seroconversion patterns to four human rotavirus serotypes in hospitalized infants with acute rotavirus gastroenteritis

We studied rotavirus-specific antibodies in paired sera from 71 hospitalized infants with acute rotavirus gastroenteritis. Most of the infants were less than six months old. Infants with serological evidence of a secondary rotavirus infection were excluded. With an enzyme-linked immunosorbent assay, 46% of the 71 infants studied showed specific IgM in convalescent sera. Titers of specific IgG and IgA increased in 7% and 2% of the infants, respectively. The presence of specific IgM correlated positively with age and severity of clinical symptoms. With a neutralization test, 59% of the infants showed a seroconversion: 20% to a single serotype (7% to serotype 1, 7% to serotype 3, and 6% to serotype 4), 21% seroconverted to two serotypes (nearly exclusively to serotypes 1 and 3), and 18% seroconverted to three serotypes (exclusively to serotypes 1, 3, and 4). No infant seroconverted to serotype 2 or to the heterologous (bovine) serotype 6.     

Prevention of human rotavirus infection with chicken egg yolk immunoglobulins containing rotavirus antibody in cat

A study was made on the passive protection against rotavirus-induced diarrhea. Chickens were immunized with bovine rotavirus (serotype 1) and the egg yolk immunoglobulins containing a high titer anti-rotavirus neutralizing antibody (CEYI) was obtained. The CEYI was then orally administered to specific-pathogen-free cats, and the cats were infected with human rotavirus. The cats treated with the CEYI remained clinically healthy after challenge, whereas diarrhea occurred in the placebo-fed cats as control. Virus antigens were detected in feces in all the diarrheal cases in the placebo-fed cats but were only sporadically detected in the CEYI-fed cats. However, the cats were only protected against rotavirus infection by the presence in the gut at the time of infection of the antibody. These results suggested that continuous administration of the CEYI is capable of preventing children from diarrhea induced by human rotavirus infection and viral shedding.     

Effects of antibody to rotavirus on protection of adults challenged with a human rotavirus

Effects of preinoculation rotavirus antibody titers on the probability of infection and illness were evaluated in adults challenged orally with different doses of a virulent human rotavirus (CJN strain). Preinoculation titers considered were serum neutralizing antibody, serum rotavirus IgA, serum rotavirus IgG, jejunal neutralizing antibody, jejunal rotavirus IgA, and stool rotavirus IgA. Doses of virus of either 9 x 10(1) or 9 x 10(3) focus-forming units were administered to 19 subjects each. Twenty-six were infected; 15 experienced illness. The probability of either outcome was unrelated to dose. Stool rotavirus IgA titers could not be correlated to either infection or illness, but the mean titers of the other five antibodies were significantly or nearly significantly lower in subjects infected or ill, when compared with those negative for either outcome. When analyzed by stepwise logistic regression, only serum rotavirus IgG remained significantly (P = .005) related to the probability of infection, and only jejunal neutralizing antibody remained significantly (P = .01) related to the probability of illness.     

Kinetics of canine antibody response to saliva of the sand fly Lutzomyia longipalpis

Zoonotic visceral leishmaniasis (VL) caused by Leishmania infantum is transmitted from dogs to humans by sand flies and Lutzomyia longipalpis is a major vector of this disease. We studied the antibody response in dogs experimentally exposed to L. longipalpis females to characterize sand fly salivary antigens recognized by canine sera and to find out whether the level of specific anti-saliva antibodies reflects the intensity of exposure. Sera from repeatedly bitten dogs revealed up to six salivary protein bands with approximate molecular weight of 66, 55, 45, 37-39, 34, and 25 kDa in L. longipalpis salivary gland lysate. Anti-saliva immunoglobin (Ig) G and its subclasses were found to be useful markers of exposure to sand flies. Specific IgG, IgG1, and IgG2 were related to numbers of bloodfed L. longipalpis females, and increased antibody levels were detectable throughout the study, i.e. more than 6 months after the last exposure. In contrast, specific IgE response developed in some dogs only, and no correlation was observed between its level and the intensity of exposure. Screening of dog sera for specific IgG against salivary antigens of the vector is suggested as a useful epidemiological tool in VL foci. Monitoring canine antibody response to sand fly saliva also allows evaluation of the effectiveness of anti-vector campaigns.