Gülden Yilmaz

Crimean-Congo hemorrhagic fever in European part of Turkey: genetic analysis of the virus strains from ticks and a seroepidemiological study in humans.

A survey of ticks from domestic ruminants, together with a serosurvey in humans was conducted in Thrace (northwestern Turkey) to evaluate the prevalence of Crimean-Congo hemorrhagic fever virus (CCHFV) in ticks and humans. More prevalent ticks were Hyalomma marginatum, Hyalomma aegyptium, Rhipicephalus bursa, and Rhipicephalus (Boophilus) annulatus, with low numbers of Dermacentor marginatus, Rhipicephalus sanguineus group, and Ixodes ricinus. No differences in the tick faunal composition were found among surveyed provinces. CCHFV was detected using specific primers for strains belonging to both Europe 1 and Europe 2 clades in a total of 15 pools of ticks collected in nine localities. The maximum likelihood estimate of infection rate was calculated as 0.72/100 ticks (95% CI = 0.42-1.16). Viral RNA was observed only in H. marginatum, R.(B.) annulatus, and R. bursa with overall maximum likelihood estimate infection rates being 0.93 (95% CI = 0.35-2.05), 0.74 (95% CI = 0.24-1.78), and 1.67 (95% CI = 0.69-3.46), respectively. The surveyed region is the only place where both viral strains are circulating together in nature in Turkey. Results from serosurvey on 193 samples from three localities in the region showed that immunoglobulin M and immunoglobulin G rates are compatible with an epidemiological situation in which the virus has been present for a long time and is not the result of a recent invasive event from the main epidemic center in Anatolia (north-central Turkey). Seropositivity rates cannot be compared against the tick faunal composition, because of the homogeneity in the results about tick surveys. The high rate of seropositivity, and the prevalence of CCHFV in both Europe 1 and 2 clades among the ticks, but few clinical cases suggest that the circulation of both viral strains may confer protection against the CCHFV infection.

Interleukin (IL)-12, IL-2, interferon-γ gene polymorphisms in subacute sclerosing panencephalitis patients

Mutated measles virus variants have been claimed as the causing agent for subacute sclerosing panencephalitis (SSPE) developing several years after the recovery from measles infection. However, immune dysfunction may be considered related to a genetic susceptibility to this rare disease. Interleukin (IL)-2 -330 (rs2069762) and +160 (rs2069763), IL-12 p40 3′ UTR (rs3213113), and interferon (IFN)-γ+874 (rs2430561) polymorphisms are screened by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and PCR-sequence-specific priming (SSP) methods in 87 SSPE patients and 106 healthy controls (HCs) as candidate genes of susceptibility. The distribution of the IL12B genotypes (rs3213113) showed a trend for a significant difference (P = .053). The frequency of IL12B C allele (P = .04, OR: 1.6) and CC genotype (P = .03, OR: 3.2) were both higher in SSPE patients than in HC. The IL2 −330 genotypes revealed lower frequencies of GG genotype (P = .03, OR: 0.4) as well as G allele (P = .02, OR: 0.6) in SSPE. IL2 −330+160 TG haplotype was more frequent in patients (P = .005, OR: 1.8), whereas GG haplotype was less frequent, compared to controls (P = .02, OR: 0.6). IFNG +874 polymorphism revealed no difference. These findings implicate possible effects of genetic polymorphisms in the susceptibility to SSPE, which need to be confirmed in other populations.

Diagnosis of HIV infection and laboratory monitoring of its therapy

BACKGROUND Serological diagnosis of human immunodeficiency virus (HIV) infection became available in 1985, with the rapid increase in sensitivity and specificity of enzyme-linked immunosorbent assays (ELISAs) and the supplement tests. Molecular tests for detection of HIV in the diagnosis of HIV infection in special settings and monitoring of HIV-1 infection followed this. OBJECTIVE AND DESIGN In this review it is intended to give a brief overview of the diagnosis and monitoring of HIV infection. RESULTS AND CONCLUSION Serological methods and molecular methods for the detection and quantitation of HIV are discussed.

Subacute sclerosing panencephalitis surveillance study in Istanbul

The exact incidence rate of subacute sclerosing panencephalitis (SSPE) in Turkey (and in Istanbul) is not known. We have conducted an active surveillance study to determine the epidemiological characteristics and the incidence rate of SSPE in Istanbul between the dates July 1, 2002 and July 1, 2004. We found that the incidence of SSPE in Istanbul is 2 per million. By logistic regression analysis, risk factors in SSPE development are determined as being at younger ages (OR: 1.199, 95%CI=1.047-1.372, P=0.009), living in crowded households (OR: 1.430, 95%CI=1.039-1.968, P=0.028), low education level of the mother (OR: 0.123, 95%CI=0.034-0.447, P=0.001), low household income (OR: 0.413, 95%CI=0.234-0.728, P=0.002), infants being born out of Marmara region (Istanbul is in Marmara region of Turkey) (OR: 0.358, 95%CI: 0.172-0.746, P=0.006), infants not being vaccinated against measles (OR: 0.495, 95%CI: 0.312-0.786), infants having had measles before (OR: 0.235, 95%CI: 0.135-0.411). As a result, it is found in this study that SSPE is mostly related to having measles infection, and measles vaccination is found to be highly protective against SSPE. This is the first epidemiological study in SSPE from Turkey that conveys the incidence rate in Istanbul.

Seroconversion after measles vaccination at nine and fifteen months of age.

Background. Despite high vaccination coverage, single dose measles immunization programs have been unsuccessful in eliminating the disease. Because seroconversion rates are lower in infants vaccinated before 12 months of age, a second dose of measles vaccine is recommended at 15 months. The aim of this study was to determine the seroconversion rates in children after the first and second doses of measles vaccinations at 9 and 15 months of age. Methods. Study population comprised 116 infants attending the Well Baby Clinic of Istanbul University, Faculty of Medicine. Serum specimens were obtained from children before and 1 month after the first measles (Rouvax, Schwarz strain 1000 TCID50) vaccine given at 9 months. A second dose was given to 72 children at 15 months of age as measles-mumps-rubella (Trimovax, Schwarz measles strain, 1000 TCID50; Urabe Am 9 mumps strain, 5000 TCID50; Wister RA 27/3 rubella strain, 1000 TCID50). Third blood samples were collected 20 months after the second vaccine. Results. Passive antibody positivity rate was 5.2% at the age of 9 months. Seroconversion rate was 77.6% after the first dose and 81.9% after the second dose of measles vaccine. Of 15 children who were seronegative, 13 (86.7%) became seropositive after the immunization at 15 months. Eleven children (19.2%) seroconverted from positive to negative after the second vaccine. Conclusion. The two dose schedule seems to increase the seropositivity rate. Our findings also indicate that increasing vaccination coverage and revaccination at 6 years of age are important even with the early two dose schedule.

Human herpes virus type 8-associated Kaposi sarcoma in a pediatric liver transplant recipient

Çeltik C, Ünüvar A, Aydoğan A, Gökçe S, Öztürk G, Güllüoğlu M, Yılmaz G, Türkoğlu S, Anak S, Sökücü S, Durmaz Ö. Human herpes virus type 8‐associated Kaposi sarcoma in a pediatric liver transplant recipient.
Pediatr Transplantation 2011: 15: E100–E104.

Granzyme B gene polymorphism associated with subacute sclerosing panencephalitis.

BACKGROUND  Subacute sclerosing panencephalitis (SSPE) is a late complication of measles infection. Immune dysfunction related to genetic susceptibility has been considered in disease pathogenesis. A functional single nucleotide polymorphism (SNP) of granzyme B gene (GZMB) reported in several pathologies may also be involved in susceptibility to SSPE. PATIENTS AND METHODS  An SNP (rs8192917, G → A, R→Q) was screened in 118 SSPE patients and 221 healthy controls (HC) by polymerase chain reaction-restriction fragment length polymorphism. Frequencies were compared between groups. In vitro production of GZMB was measured in controls with different genotypes. RESULTS  The SNP had a minor allele (G) frequency of 0.22 in patients and 0.31 in controls. GG genotype was significantly less frequent in patients (odds ratio, 0.23). G allele carriers produced relatively higher levels of GZMB, when stimulated in vitro. CONCLUSION  These findings implicate possible effect of this genetic polymorphism in susceptibility to SSPE which needs to be confirmed in bigger populations.