Recent change in the annual pattern of sexually transmitted diseases in the United States

This study analyzed the 1999 to 2003 database of the Center for Disease Control and Prevention (CDC) for seasonal and longer-term time trends in the sexually transmitted diseases (STDs) of chlamydia, gonorrhea, and syphilis in the United States. Linear regression was used to ascertain time trends, and a linear mixed auto-regression model was applied to determine the statistical significance of the major peaks relative to the annualized time series mean. A statistically significant increasing trend during the 5 yr span was documented only in the incidence of chlamydia. No clear annual periodicity was detected in any of the STDs; instead, significant three-month cycles were documented in all the STDs, with prominent peaks evident in March, May, August, and November. The March and May peaks could be associated with the sexual activities of young adults during spring break, which for different colleges and universities, commences as early as mid- to late-February and concludes as late as early- to mid-April, when huge numbers of sexually active youth congregate at beach resort settings. We propose the August peak is representative of summer sexual activity, in particular, of youths during school recess when adult supervision is poor. Finally, the autumn peak seems to be an expression of an endogenous annual rhythm in human reproductive biology, exemplified by elevated levels of testosterone in young males and sexual activity at this time of the year.     

Seasonality of Primarily Childhood and Young Adult Infectious Diseases in the United States

The Center for Disease Control (CDC) in the United States collects and maintains records of communicable (so‐called notifiable) infectious diseases that cause significant morbidity and mortality and impact the national economy. This investigation focused on seasonal patterns in the primarily childhood and young adult infectious diseases of meningococcal meningitis, mumps, pertussis, typhoid fever, streptococcal toxic shock syndrome (1990 to 2003 CDC database), and varicella (1993 to 2003 CDC database). Linear regression was performed to ascertain the trend in the incidence of each disease, and multi‐component cosinor analysis was applied to determine and describe periodicities. Significant decreasing trends in incidence were detected in meningococcal meningitis, mumps, typhoid fever, and streptococcal toxic shock syndrome, and increasing trends were found in pertussis and varicella. Significant annual patterns were documented in meningococcal meningitis (January peak), mumps (April peak), pertussis (August peak), varicella (April peak), typhoid fever (August peak), and in the hospital‐acquired streptococcal toxic shock syndrome (February peak). Such seasonal patterns and long‐term trends in infectious diseases are of practical public health significance in indicating which can benefit from timely prevention interventions.     

Seasonality of primarily childhood and young adult infectious diseases in the United States

The Center for Disease Control (CDC) in the United States collects and maintains records of communicable (so-called notifiable) infectious diseases that cause significant morbidity and mortality and impact the national economy. This investigation focused on seasonal patterns in the primarily childhood and young adult infectious diseases of meningococcal meningitis, mumps, pertussis, typhoid fever, streptococcal toxic shock syndrome (1990 to 2003 CDC database), and varicella (1993 to 2003 CDC database). Linear regression was performed to ascertain the trend in the incidence of each disease, and multi-component cosinor analysis was applied to determine and describe periodicities. Significant decreasing trends in incidence were detected in meningococcal meningitis, mumps, typhoid fever, and streptococcal toxic shock syndrome, and increasing trends were found in pertussis and varicella. Significant annual patterns were documented in meningococcal meningitis (January peak), mumps (April peak), pertussis (August peak), varicella (April peak), typhoid fever (August peak), and in the hospital-acquired streptococcal toxic shock syndrome (February peak). Such seasonal patterns and long-term trends in infectious diseases are of practical public health significance in indicating which can benefit from timely prevention interventions.     

STD患者及性高危人群泌尿生殖道支原体感染状况研究

目的:探讨泌尿生殖道支原体在STD患者及性高危人群中的感染状况.方法:采用培养法对421例STD患者、84例性乱者和185例性病伴侣进行解脲脲原体(Uu)和人型支原体(Mh)的检测.结果:STD患者、性乱者和性病伴侣泌尿生殖道支原体感染率分别为42.28%、35.71%和40.0%,与健康人群(13.48%)比较,差异有显著性(x2=56.61、19.44、38.16,P＜0.005).前三者之间比较,差异无显著性(x2=1.25、0.28、0.45,P＞0.05).Uu感染率(15.22%)与Mh(5.22%)比较,前者明显高于后者(x2=37.61,P＜0.005).男性Uu和Mh感染率(分别为8.57%、2.08%)与女性(分别为23.61%、9.18%)比较,女性明显高于男性(x2=29.82、17.36,P＜0.005).Uu和Mh混合感染率(20.43%)明显高于Uu(15.22%)或Mh(5.22%)的单独感染率(x2=6.41、71.45,P值分别为P＜0.05、P＜0.005).结论:Uu和Mh在STD患者、性乱者和性病伴侣中流行、感染率高,在性病的防治和监测工作中应加以重视.     

Sexual Behavior and Network Characteristics and Their Association with Bacterial Sexually Transmitted Infections among Black Men Who Have Sex with Men in the United States

Background

Black men who have sex with men (MSM) have a high prevalence of bacterial sexually transmitted infections (STIs), and individual risk behavior does not fully explain the higher prevalence when compared with other MSM. Using the social-ecological framework, we evaluated individual, social and sexual network, and structural factors and their association with prevalent STIs among Black MSM.

Methods

The HIV Prevention Trials Network 061 was a multi-site cohort study designed to determine the feasibility and acceptability of a multi-component intervention for Black MSM in six US cities. Baseline assessments included demographics, risk behavior, and social and sexual network questions collected information about the size, nature and connectedness of their sexual network. Logistic regression was used to estimate the odds of having any prevalent sexually transmitted infection (gonorrhea, chlamydia, or syphilis).

Results

A total of 1,553 Black MSM were enrolled in this study. In multivariate analysis, older age (aOR = 0.57; 95% CI 0.49–0.66, p<0.001) was associated with a lower odds of having a prevalent STI. Compared with reporting one male sexual partner, having 2–3 partners (aOR = 1.74; 95% CI 1.08–2.81, p<0.024) or more than 4 partners (aOR = 2.29; 95% CI 1.43–3.66, p<0.001) was associated with prevalent STIs. Having both Black and non-Black sexual partners (aOR = 0.67; 95% CI 0.45–0.99, p = 0.042) was the only sexual network factor associated with prevalent STIs.

Conclusions

Age and the number and racial composition of sexual partners were associated with prevalent STIs among Black MSM, while other sexual network factors were not. Further studies are needed to evaluate the effects of the individual, network, and structural factors on prevalent STIs among Black MSM to inform combination interventions to reduce STIs among these men.     

A Change in Vaccine Efficacy and Duration of Protection Explains Recent Rises in Pertussis Incidence in the United States

Over the past ten years the incidence of pertussis in the United States (U.S.) has risen steadily, with 2012 seeing the highest case number since 1955. There has also been a shift over the same time period in the age group reporting the largest number of cases (aside from infants), from adolescents to 7–11 year olds. We use epidemiological modelling and a large case incidence dataset to explain the upsurge. We investigate several hypotheses for the upsurge in pertussis cases by fitting a suite of dynamic epidemiological models to incidence data from the National Notifiable Disease Surveillance System (NNDSS) between 1990–2009, as well as incidence data from a variety of sources from 1950–1989. We find that: the best-fitting model is one in which vaccine efficacy and duration of protection of the acellular pertussis (aP) vaccine is lower than that of the whole-cell (wP) vaccine, (efficacy of the first three doses 80% [95% CI: 78%, 82%] versus 90% [95% CI: 87%, 94%]), increasing the rate at which disease is reported to NNDSS is not sufficient to explain the upsurge and 3) 2010–2012 disease incidence is predicted well. In this study, we use all available U.S. surveillance data to: 1) fit a set of mathematical models and determine which best explains these data and 2) determine the epidemiological and vaccine-related parameter values of this model. We find evidence of a difference in efficacy and duration of protection between the two vaccine types, wP and aP (aP efficacy and duration lower than wP). Future refinement of the model presented here will allow for an exploration of alternative vaccination strategies such as different age-spacings, further booster doses, and cocooning.     

延边地区丙型肝炎患者合并TT病毒感染的检测

检测丙型肝炎患者血清标本中的TT病毒 (transfusiontransmittedvirus,TTV) ,了解延边地区丙型肝炎患者合并TTV感染状况。采用ELISA检测抗TTVIgG和巢式PCR检测丙型肝炎病毒 (HCV)感染患者血清中TTVDNA。采用全自动生化分析仪检测患者血清谷氨酸氨基转移酶 (ALT)和谷氨酸草酰乙酸氨基转移酶 (AST)。 4 5例丙型肝炎患者抗TTVIgG阳性率为 37.8% (17/45 ) ,巢式PCR阳性率为 4 2 .2 % (19/45 )。延边地区HCV感染患者重叠感染TTV较常见。     

冬凌草甲素抗炎作用参与多种疾病治疗的新进展

冬凌草甲素是冬凌草的主要活性成分,具有广泛的药理作用。研究表明,冬凌草甲素在炎症性疾病方面表现出较好的疗效。综述国内外关于冬凌草甲素抗炎作用参与多种疾病治疗的研究进展,并分析研究的方向,为研究与开发以冬凌草为原料的抗炎新药提供参考。     

Seasonal variations in the responses of glycolytic intermediates of human erythrocytes to acute cold exposure

Seven male students were studied to observe the effects of acute cold exposure (at 10°C for 60 min) on erythrocyte concentrations of glycolytic intermediates in summer and in winter. The subjects shivered slightly but frankly in both experiments. Significant decreases were observed in the concentrations of pyruvate and lactate during body cooling in summer, but not in winter. The lactate concentration remained significantly reduced 15 min after cold exposure. After 60 min of cold exposure in summer, a negative crossover point appeared to exist between phosphoenolpyruvate and pyruvate and erythrocyte pyruvate kinase activity showed a significant decrease. No seasonal difference was observed in the initial control values of the intermediates measured. From these results and the fact that glucose, pyruvate and lactate are evenly distributed between erythrocytes and plasma, it is likely that erythrocytes and skeletal muscles need less fuel substrate, glucose during cold exposure in winter than in summer, suggesting that an increased economy of energy for homeostasis is achieved.     

2017: beginning of a new era for Chlamydia research in China and the rest of the world

The First Chinese Chlamydia Research Meeting was held in Lanzhou, China in May 2017, 60 years after the disclosure of reproducible isolation of Chlamydia trachomatis by 汤飞凡 (Fei-fan Tang). We report current state of the Chlamydia research community in China, and briefly review recent progress in Chlamydia vaccinology. The meeting represents a new milestone for Chlamydia research in the country. The Chinese Chlamydia Research Society (CCRS) was formed during the meeting. Future meetings will be held biennially and should facilitate collaboration of Chinese researchers with their domestic and international colleagues.     

Taxonomic and Biological Characterization of Steinernema rarum Found in the Southeastern United States

Two Steinernema isolates found in Louisiana and Mississippi were later identified as isolates of S. rarum. DNA sequences of ITS regions of the United States isolates are identical with sequences of Argentinean S. rarum strains Samiento and Noetinger and differ by two bases from the Arroyo Cabral isolate from Córdoba, Argentina. SEM observations revealed several new structures in the isolates from the US: female face views have a hexagonal-star perioral disc and eye-shaped lips; some females do not have cephalic papillae; lateral fields of infective juveniles are variable; there are two openings observed close to the posterior edge of the cloaca. Virulence of the US isolates to Anthonomus grandis, Diaprepes abbreviatus, Solenopsis invicta, Coptotermes formosanus, Agrotis ipsilon, Spodoptera frugiperda, and Trichoplusia ni and reproductive potential were evaluated in comparison with other heterorhabditid and steinernematid nematodes. Results such as particularly high virulence to S. frugiperda indicate that the biocontrol potential of the new S. rarum strains merits further study.     

The effects of monthly temperature fluctuations on mortality in the United States from 1921 to 1985

The impact of short-term temperature fluctuations on mortality has been studied mainly on historical populations, thus providing a limited ability to generalize to contemporary conditions, which would be more useful in determining public health policies aimed at reducing mortality. Therefore, this study examined the effects of monthly temperature fluctuations on mortality in the United States from 1921 to 1985. Monthly data about mortality from the Vital Statistics and temperature from the National Oceanic and Atmospheric Administration and the US Department of Agriculture Weather Bureau were used. Six states were selected to be studied (Massachusetts, Michigan, Washington, Utah, North Carolina, and Mississippi). The analysis was carried out using distributed lag models. The analysis-showed that warmer than usual temperatures in July and August, and unusually cold temperatures from January to June are linked to higher mortality. From September to December unusually low temperatures are associated with higher mortality in most states, while temperature has no significant effect on mortality in June and September. In January and February mortality is especially affected by unusually cold weather in the southern states of Mississippi and North Carolina. For example, a one degreee drop in the mean temperature in 1921 is associated with a more than 3.5% increase in the February crude death rate in Mississippi and North Carolina and a less than 1% increase in the four other states examined. Finally, in the months from January to March the relationship between monthly fluctuations in the crude death rate and temperature declined over time and became relatively weak by 1985.     

A review of vertebrate community composition in seasonal forest pools of the northeastern United States

Seasonally-flooded wetlands occur throughout the world and provide important foraging, resting, and breeding habitat for a broad array of organisms. This review summarizes our current understanding of vertebrate community composition at seasonal forest pools in the northeastern United States. These wetlands typically have hydroperiods that range from temporarily flooded to intermittently exposed, which reduces densities of many potential predators (e.g., fish). Current research has shown that pool hydroperiod, canopy closure, vegetation structure within pools, presence of potential predators, and landscape structure surrounding pools are the key factors determining vertebrate diversity at seasonal forest pools. Of 25 species of amphibians in the region, frogs (10 of 12 species) are more likely to breed in seasonal forest pools than salamanders (6 of 13 species). Seven of 10 amphibian species that breed in seasonal forest pools are state-listed as threatened or endangered. Among 27 species of reptiles, 3 of 15 species of snakes, and 6 of 12 species of turtles utilize seasonal pools during at least one stage of their annual cycle. Seasonal forest pools are important foraging and basking habitat for three species of turtles listed as threatened or endangered. Compared to other vertebrate taxa, most species of mammals are habitat generalists, with 50 of 63 mammal species potentially foraging at seasonal pools during part of their annual cycle. Chiroptera (bats; all 9 species) are believed to actively forage at seasonal pools and some Insectivora, particularly Sorex palustris Richardson and S. fumeus (Miller) and Condylura cristata (L.), are detected regularly at seasonal pools. Breeding birds are less likely to utilize seasonal pools than other vertebrate taxa, although 92 of 233 species might forage or breed near seasonal pools. Several species of Anatidae, Rallidae, and some Passeriformes use seasonally flooded pools. All vertebrates that use seasonal forest pools use other habitats during some stage in their life cycle; thus gaining a clear understanding of their habitat requirements is critical to their long-term persistence.     

Diseases diagnosed in wild turkeys (Meleagris gallopavo) of the southeastern United States

Diagnostic findings are presented on 139 sick or dead wild turkeys examined during the period 1972 through 1984. Turkeys originated from eight southeastern states (Alabama, Arkansas, Florida, Georgia, South Carolina, Tennessee, Virginia, West Virginia) and included 31 turkeys categorized as capture-related mortalities and 108 turkeys categorized as natural mortalities. Frequent diagnoses (greater than or equal to 10% of case accessions) in the natural mortality group were trauma, avian pox, and histomoniasis. Less frequent diagnoses (less than or equal to 4% of case accessions) included malnutrition/environmental stress syndrome, coligranuloma-like condition, crop impaction, bumblefoot, organophosphate toxicosis, infectious sinusitis, a lympho-proliferative disease, salmonellosis, aspergillosis, toxoplasmosis, crop trichomoniasis, and melorheostosis.     

Ecological correlates of risk and incidence of West Nile virus in the United States

West Nile virus, which was recently introduced to North America, is a mosquito-borne pathogen that infects a wide range of vertebrate hosts, including humans. Several species of birds appear to be the primary reservoir hosts, whereas other bird species, as well as other vertebrate species, can be infected but are less competent reservoirs. One hypothesis regarding the transmission dynamics of West Nile virus suggests that high bird diversity reduces West Nile virus transmission because mosquito blood-meals are distributed across a wide range of bird species, many of which have low reservoir competence. One mechanism by which this hypothesis can operate is that high-diversity bird communities might have lower community-competence, defined as the sum of the product of each species’ abundance and its reservoir competence index value. Additional hypotheses posit that West Nile virus transmission will be reduced when either: (1) abundance of mosquito vectors is low; or (2) human population density is low. We assessed these hypotheses at two spatial scales: a regional scale near Saint Louis, MO, and a national scale (continental USA). We found that prevalence of West Nile virus infection in mosquito vectors and in humans increased with decreasing bird diversity and with increasing reservoir competence of the bird community. Our results suggest that conservation of avian diversity might help ameliorate the current West Nile virus epidemic in the USA     

Climate Change Effects on Vegetation Distribution and Carbon Budget in the United States

The Kyoto protocol has focused the attention of the public and policymarkers on the earth's carbon (C) budget. Previous estimates of the impacts of vegetation change have been limited to equilibrium “snapshots” that could not capture nonlinear or threshold effects along the trajectory of change. New models have been designed to complement equilibrium models and simulate vegetation succession through time while estimating variability in the C budget and responses to episodic events such as drought and fire. In addition, a plethora of future climate scenarios has been used to produce a bewildering variety of simulated ecological responses. Our objectives were to use an equilibrium model (Mapped Atmosphere–Plant–Soil system, or MAPSS) and a dynamic model (MC1) to (a) simulate changes in potential equilibrium vegetation distribution under historical conditions and across a wide gradient of future temperature changes to look for consistencies and trends among the many future scenarios, (b) simulate time-dependent changes in vegetation distribution and its associated C pools to illustrate the possible trajectories of vegetation change near the high and low ends of the temperature gradient, and (c) analyze the extent of the US area supporting a negative C balance. Both models agree that a moderate increase in temperature produces an increase in vegetation density and carbon sequestration across most of the US with small changes in vegetation types. Large increases in temperature cause losses of C with large shifts in vegetation types. In the western states, particularly southern California, precipitation and thus vegetation density increase and forests expand under all but the hottest scenarios. In the eastern US, particularly the Southeast, forests expand under the more moderate scenarios but decline under more severe climate scenarios, with catastrophic fires potentially causing rapid vegetation conversions from forest to savanna. Both models show that there is a potential for either positive or negative feedbacks to the atmosphere depending on the level of warming in the climate change scenarios. Received 12 May 2000; accepted 22 November 2000.     

On some formulas in a partnership model from the perspective of a semi-Markov process

Many deterministic models of sexually transmitted diseases, as well as population models in general, contain elements of stochastic or statistical reasoning. An example of such a model is that of Dietz and Hadeler (1988) concerning sexually transmitted diseases in which there is partnership formation and dissolution. Among the interesting formulas in this paper, which enter into the analysis of the model, are those for the expected number of partners a male or female has during a lifetime. To a probabilist such formulas suggest the possibility that some stochastic process may be constructed so as to yield these formulas as well as others that may be of interest. The principal purpose of this paper is to demonstrate that such a stochastic process does indeed exist in the form of a three state semi-Markov process in continuous time with stationary laws of evolution and with a one-step density matrix determined by four parameters which were interpreted as constant latent risk functions in the classical theory of competing risks. This construction of a semi-Markov process not only provides a framework for the systematic derivation of the formulas of Dietz and Hadeler but also suggests pathways,for extensions to the age-dependent case.This research was partially supported by NATO Grant D.890350     

APOA1 gene polymorphisms in the South Asian immigrant population in the United States

BACKGROUND:

Coronary artery disease (CAD) is a leading cause of death in the United States. South Asian immigrants (SAIs) from the Indian subcontinent living in the US are disproportionately at higher risk of CAD than other immigrant populations. Unique genetic factors may predispose SAIs to increased risk of developing CAD when adopting a Western lifestyle including a higher-fat diet, more sedentary behavior and additional gene-environment interactions. SAIs are known to have low levels of the protective high density lipoprotein (HDL) and an altered function for Apo-lipoprotein A-1 (ApoA1), the main protein component of HDL cholesterol. One gene that may be genetically distinctive in this population is APOA1 which codes for ApoA-1 protein, a potentially important contributing factor in the development of CAD.

MATERIALS AND METHODS:

DNA sequencing was performed to determine the status of the seven single-nucleotide polymorphisms (SNPs) in the APOA1 gene from 94 unrelated SAI adults. Genotypes, allelic frequencies, and intragenic linkage disequilibrium of the APOA1 SNPs were calculated.

RESULTS:

Several polymorphisms and patterns were common among persons of south Asian ethnicity. Frequencies for SNPs T655C, T756C and T1001C were found to be different than those reported in European Caucasian individuals. Linkage disequilibrium was found to be present between most (13 of 15) SNP pairings indicating common inheritance patterns.

CONCLUSIONS:

SAIs showed variability in the sequence of the APOA1 gene and linkage disequilibrium for most SNPS. This pattern of APOA1 SNPs may contribute to decreased levels of HDL cholesterol reported in SAIs, leading to an increased risk for developing CAD in this population.