Lipschutz Ulcer in A Virgin Woman: A Case Report

Background: Lipschutz ulcer, also known as vulvae acutum ulcer, is an acute ulcer in the vulva. The aetiology and pathogenesis of Lipschutz ulcer are unclear, but it is known to be associated with infectious diseases such as Mycoplasma infection, paratyphoid fever, influenza A, and most infections with Epstein-Barr virus (EBV). This ulcer appears in adolescent females aged 14–20 years old, with 70% of cases occurring in virgin women. Purpose: To review the causes of non-Sexually Transmitted Diseases (STD) ulcers, so clinicians can establish an accurate diagnosis and rational therapy; therefore, minimizing the psychological impact on the patient due to possible misdiagnosis of STD-induced ulcer. Case: A painful wound in the genital area of a 20-year-old virgin woman. She was diagnosed with Lipshutz ulcer and vulvovaginal candidiasis based on the anamnesis, physical examination, and laboratory examination obtained from vaginal discharge using potassium hydroxide, Gram staining, and blood test to exclude genital ulcer caused by the sexually transmitted agent. A blood test was taken, including the serological tests for syphilis and genital herpes. Tests for EBV were also performed. The patient was treated only with single-dose fluconazole 150 mg orally and saline compress on the ulcer. Genital ulcer and vaginal discharge improved one week after treatment. Discussion: Lipshutz ulcer management is symptomatic, usually self-limiting, and disappears spontaneously within 1–2 weeks without recurrences. It can also occur as a single lesion with possible coinfection of other agents, for example, candidiasis, which in this case, requires treatment of comorbidities. Hygiene factors play an essential role in preventing occurrence of the secondary infection and further development of the disease. Conclusion: The diagnosis of Lipshutz ulcer is mainly based on clinical manifestation after excluding several possible ulcers that can affect the genital area, including sexually transmitted infections.

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Etiology of Genital Ulcer Disease in Dakar, Senegal, and Comparison of PCR and Serologic Assays for Detection of Haemophilus ducreyi

Journal of Clinical Microbiology ◽

10.1128/jcm.38.1.268-273.2000 ◽

2000 ◽

Vol 38 (1) ◽

pp. 268-273

Author(s):

Patricia A. Totten ◽

Jane M. Kuypers ◽

Cheng-Yen Chen ◽

Michelle J. Alfa ◽

Linda M. Parsons ◽

...

Keyword(s):

Transmitted Disease ◽

Haemophilus Ducreyi ◽

Genital Ulcer ◽

Serological Tests ◽

Past Infection ◽

Ulcer Disease ◽

Sexually Transmitted ◽

Genital Ulcer Disease ◽

Pcr Assays ◽

Simplex Virus

ABSTRACT We used PCR assays to determine the etiology of genital ulcers in patients presenting to a sexually transmitted disease clinic in Dakar, Senegal, and evaluated the ability of two PCR tests ( groEL and recD ) and two serological tests (adsorption enzyme immunoassay [EIA] and lipooligosaccharide [LOS] EIA) to detect current Haemophilus ducreyi infection. We found that in this population, H. ducreyi , T. pallidum , and herpes simplex virus HSV DNA were detected in 56, 15, and 13% of 39 genital ulcer specimens, respectively, and H. ducreyi DNA was detected in 60% (3 of 5) of samples from ulcerated bubos. Among 40 consecutive patients with genital ulcer disease and with sufficient sample for both PCR assays, the recD and groEL H. ducreyi PCR assays were 83% concordant, with the recD PCR assay detecting six (15%) additional positive specimens and the groEL assay detecting one (3%) additional positive specimen. Compared to PCR, the adsorption EIA and LOS EIA tests had sensitivities of 71 and 59% and specificities of 57 and 90%, respectively, for the diagnosis of current H. ducreyi infection. While these differences in specificity could be due either to previous infection with H. ducreyi or to the detection of cross-reacting antibodies, only 6% of patients from a nearby family planning clinic gave a positive reaction in both the adsorption EIA and LOS EIA assays, indicating that cross-reacting antibodies are not prevalent among clinic attendees in this city. Our studies indicate that the adsorption EIA detects both current and past infection, while the LOS EIA assay is more specific for current infection with H. ducreyi in this population.

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Aetiology of sexually transmitted infections in Maputo, Mozambique

The Journal of Infection in Developing Countries ◽

10.3855/jidc.1179 ◽

2010 ◽

Vol 5 (01) ◽

pp. 041-047 ◽

Cited By ~ 8

Author(s):

Tomas Francisco Zimba ◽

Teke Apalata ◽

Willem Adrian Sturm ◽

Prashini Moodley

Keyword(s):

Vaginal Discharge ◽

Genital Ulcer ◽

Transmitted Infection ◽

Syndromic Management ◽

Sexually Transmitted ◽

Genital Ulcers ◽

Simplex Virus ◽

Syphilis Serology ◽

Hiv 1

Introduction: The study sought to ascertain the prevalence of the aetiological agents of genital discharge and genital ulcer diseases in Maputo, Mozambique. Methodology: Consecutive consenting patients presenting to the Centro de Saúde do Porto in Maputo between March and April 2005 with genital discharge syndrome and/or genital ulcer diseases were recruited. Specimens were collected for the identification of STI pathogens. Results: Of 346 recruited patients, 164 were male and 182 female. The prevalence of confirmed single aetiological agents for male urethritis was as follows: N. gonorrhoeae, 35%; C. trachomatis, 10%; and M. genitalium 4%. For vaginal discharge, N. gonorrhoeae was found in11% of the women tested, followed by C. trachomatis (6.5%), bacterial vaginosis (34%), and T. vaginalis (2%). The prevalence of genital ulcers was as follows: Herpes simplex virus type 2, 62%; H. ducreyi 4 %; and C. trachomatis biovar LGV, 4%. Five percent of patients with genital ulcers had a positive syphilis serology (RPR ≥ 1:8 and confirmed by TPHA) and 35% of all tested patients were HIV-1/2 infected. Cases of mixed infections were present in 5%, 11% and 3% of patients with male urethritis, vaginal discharge, and genital ulcers respectively. Conclusion: The classic sexually transmitted infection aetiologies are still prevalent in Maputo. The study highlights the need for a periodic surveillance to inform syndromic management protocols.

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Recent Trends of Syndromic Sexually Transmitted Infections at a Tertiary Care Center in Maharashtra, India: A Retrospective Analysis

Journal of Skin and Stem Cell ◽

10.5812/jssc.112709 ◽

2021 ◽

Vol 8 (2) ◽

Author(s):

Ravindranath Brahmadeo Chavan ◽

Vasudha Abhijit Belgaumkar ◽

Nitika S. Deshmukh ◽

Ranjitha Krishnegowda

Keyword(s):

Abdominal Pain ◽

Sexually Transmitted Infections ◽

Vaginal Discharge ◽

Tertiary Care ◽

Lower Abdominal Pain ◽

Genital Ulcer ◽

Care Hospital ◽

Ulcer Disease ◽

Sexually Transmitted ◽

Genital Ulcer Disease

Background: Sexually transmitted infections (STIs) constitute a major public health problem in both developed and developing countries. Human immunodeficiency virus (HIV) and STIs are linked in their similar mode of transmission, with STIs facilitating the acquisition and transmission of HIV. The prevalence pattern of individual STIs may evolve over time necessitating a corresponding change in management strategies. Objectives: The study was conducted to determine the burden and any change in the etiological trend among attendees of an STIs clinic at a tertiary care hospital. Methods: This retrospective study analyzed data retrieved from consecutive patients attending an STIs clinic over two years (July 2018 to July 2020). Results: Overall, 1916 patients were diagnosed with STIs. The predominant age group was 25 - 44 years (59.23%). Genital ulcer disease was the foremost syndrome (1213, 63.3%). Overall, herpetic genital ulcer was the most common (682, 35.6%), followed by non-herpetic ulcers (531, 27.7%). Vaginal discharge, lower abdominal pain, and urethritis were found in 461 (24%), 219 (11.43%), and 23 (1.27%) of the patients, respectively. Amongst 237 (12.36%) In HIV seropositive attendees, genital ulcer disease (herpetic) was the most common syndrome (179, 75.53%), followed by vaginal discharge (42, 17.72%), lower abdominal pain (9, 3.8%), and urethritis (7, 2.9%). Conclusions: A definite change in the profile of STIs was observed with ulcerative STIs (particularly herpes genitalis) constituting the major burden against a discernible back drop of decreasing non-herpetic STIs. A systematic, regional, periodic synopsis would not only help to follow and document the dynamic trends, but also can help to assess the effectiveness of control programs.

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COVID-19 Seroprevalence among Healthcare Workers of a Large COVID-19 Hospital in Rome Reveals Strengths and Limits of Two Different Serological Tests

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18052650 ◽

2021 ◽

Vol 18 (5) ◽

pp. 2650

Author(s):

Giuseppe Vetrugno ◽

Daniele Ignazio La Milia ◽

Floriana D’Ambrosio ◽

Marcello Di Pumpo ◽

Roberta Pastorino ◽

...

Keyword(s):

Blood Test ◽

Healthcare Workers ◽

Point Of Care ◽

Venous Blood ◽

Administrative Staff ◽

Serological Tests ◽

Predictive Values ◽

Work From Home ◽

Significant Difference ◽

Sensitivity Specificity

Healthcare workers are at the forefront against COVID-19, worldwide. Since Fondazione Policlinico Universitario A. Gemelli (FPG) IRCCS was enlisted as a COVID-19 hospital, the healthcare workers deployed to COVID-19 wards were separated from those with limited/no exposure, whereas the administrative staff were designated to work from home. Between 4 June and 3 July 2020, an investigation was conducted to evaluate the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin (IgG) antibodies among the employees of the FPG using point-of-care (POC) and venous blood tests. Sensitivity, specificity, and predictive values were determined with reverse-transcription polymerase chain reaction on nasal/oropharyngeal swabs as the diagnostic gold standard. The participants enrolled amounted to 4777. Seroprevalence was 3.66% using the POC test and 1.19% using the venous blood test, with a significant difference (p < 0.05). The POC test sensitivity and specificity were, respectively, 63.64% (95% confidence interval (CI): 62.20% to 65.04%) and 96.64% (95% CI: 96.05% to 97.13%), while those of the venous blood test were, respectively, 78.79% (95% CI: 77.58% to 79.94%) and 99.36% (95% CI: 99.07% to 99.55%). Among the low-risk populations, the POC test’s predictive values were 58.33% (positive) and 98.23% (negative), whereas those of the venous blood test were 92.86% (positive) and 98.53% (negative). According to our study, these serological tests cannot be a valid alternative to diagnose COVID-19 infection in progress.

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Co-infection with genital gonorrhoea and genital chlamydia in female sex workers in Yunnan, China

International Journal of STD & AIDS ◽

10.1258/095646206776790088 ◽

2006 ◽

Vol 17 (5) ◽

pp. 329-332 ◽

Cited By ~ 14

Author(s):

Xiang-Sheng Chen ◽

Yue-Ping Yin ◽

Guo-Jun Liang ◽

Xiang-Dong Gong ◽

Hua-Sheng Li ◽

...

Keyword(s):

Sex Workers ◽

Female Sex Workers ◽

Vaginal Discharge ◽

Transmitted Disease ◽

Clinical Information ◽

Gonococcal Infection ◽

Structured Interviews ◽

Sexually Transmitted ◽

Female Sex ◽

Control Programmes

An observational study on prevalence of co-infection with gonorrhoea and chlamydia was conducted among female sex workers (FSWs) in Kunming, China. A total of 505 FSWs participated in the study. All eligible participants gave informed consent. Demographic, behavioural and clinical information of the participants was gathered by direct structured interviews. Tampon swabs were collected to test for Chlamydia trachomatis and Nesseria gonorrhoeae. One-hundred and twenty-four (24.6%) FSWs were co-infected with these two pathogens. Of the 191 FSWs with gonorrhea, 124 (64.9%, 95% confidence interval [CI] = 57.9–71.3%) were co-infected with chlamydia which was significantly higher than the proportion (41.9%, 95% CI = 36.4–47.6%) co-infected with gonorrhoea among 296 FSWs with chlamydia ( P < 0.001). Only 47 of 191 (24.6%) FSWs with gonococcal infection and 28 of 124 (22.6%) with co-infection with gonorrhoea and chlamydia reported vaginal discharge. The results of the study justify the recommendation in the national sexually transmitted disease (STD) guidelines that patients infected with gonorrhoea also be treated routinely with an anti-chlamydial regimen. However, a periodic mass treatment may be considered in some circumstances in STD control programmes to rapidly reduce the infections in this population.

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Some viral, rickettsial and leptospiral infections diagnosed in Serbia. A serological study

Journal of Hygiene ◽

10.1017/s0022172400027340 ◽

1954 ◽

Vol 52 (2) ◽

pp. 129-150 ◽

Cited By ~ 5

Author(s):

A. L. Terzin ◽

M. N. BordjoŠki ◽

M. V. Milovanović ◽

Lj. V. Stojković ◽

M. M. Dimić

Keyword(s):

Infectious Diseases ◽

Infectious Mononucleosis ◽

Influenza A ◽

Q Fever ◽

Soluble Antigen ◽

Serological Tests ◽

Marked Rise ◽

Cold Agglutinins ◽

Type Antigen ◽

Virus Pneumonia

An analysis is given of the serological tests performed over a period of 15 months with viral, rickettsial and leptospiral antigens. The analysed material is made up of about 9400 tests performed on 4036 samples of serum obtained from 2430 patients and 536 animals.The incidence of the various diseases, the distribution of the positive results according to diseases, and the height of the specific titres, as well as the height of the residual titres found in the material, are discussed and analysed in detail.The procedure for the preliminary screening of the material, as well as the methods used in performing the different serological tests, are described and discussed.A few examples of possible double infections are quoted, namely atypical virus pneumonia with influenza, and influenza A with B.An analysis of the results of 1723 tests performed with influenza antigens on 909 samples of sera is presented.The results obtained from testing about 1000 sera for cold agglutinins and 482 sera for MG agglutinins are discussed in detail.Some cases of liver affections showed a marked rise in titre both of cold agglutinins and of MG agglutinins.The serum samples, numbering about 1050, drawn from normal persons or patients suffering from infections other than Q-fever, all gave titres lower than 1/64 when tested with Q-fever antigen, except the sera of four persons who were probably cases of recent inapparent infection.The geometrical mean of the titres found in sera drawn from acute Q-fever patients between the 29th and 60th days of their illness was 1/355. Of the 500 sera from various animals, 100 from sheep and eight from cows had titres of 1/8 to 1/64 against the Q-fever antigen.Thirty-four sera have been positive when tested with the soluble antigen of both the epidemic and the murine types of typhus but no serum has given a higher titre with the murine type antigen than with the epidemic type antigen. Of the thirty-four sera tested with both antigens the titres obtained with the epidemic antigen were higher than with the murine antigen in 28.The results obtained with 417 sera tested with the mumps antigen, and with the 222 sera tested with the lymphocytic choriomeningitis antigen are reported and discussed in detail.Great individual variation has been observed in the time of appearance and rise and fall of the Paul-Bunell titres. Consequently, it is advised that early and frequent blood samples should be obtained from patients who are suspected to be suffering from infectious mononucleosis. On the basis of the results of 316 Paul-Bunnell tests it is suggested that a titre of 1/20, if preceded or followed by a negative serum sample, should be taken as conclusive evidence of infectious mononucleosis.3080 human and 164 animal sera have been investigated for the presence of antibodies to various types of leptospirae. In both human and animal sera antibodies have been found most frequently against L. sejroe and L. pomona.The results of a few tests performed with toxoplasma antigen are mentioned briefly.We wish to express our gratitude to all our colleagues in Belgrade and other parts of the country who have provided us with information and additional samples of blood when requested, in particular Prof. K. Todorowich of the Infectious Diseases Hospital, Belgrade, and Drs Lj. Vuksich, M. Morelj, B. Arsich, D. Mehl and R. Papo of the Army Medical School, Belgrade.We wish to thank Dr R. Djorich of the Infectious Diseases Hospital, Belgrade, for the supply of material for testing for atypical virus pneumonia and aseptic meningitis, and Dr Ž. Perishich for help with our cases of infectious mononucleosis. Mrs Martha Milivojevich gave valuable assistance with the complement-fixation tests and with the compilation of material for this report.

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Aetiology of vaginal discharge in children

International Journal of Research in Dermatology ◽

10.18203/issn.2455-4529.intjresdermatol20170502 ◽

2017 ◽

Vol 3 (1) ◽

pp. 83

Author(s):

Parimalam Kumar ◽

Suguna K. ◽

Lavanya P.

Keyword(s):

Vaginal Discharge ◽

Descriptive Analysis ◽

Age Groups ◽

Juvenile Diabetes ◽

Sexually Transmitted ◽

Anatomy And Physiology ◽

History Of ◽

Group A ◽

Aetiological Diagnosis ◽

Anti Fungal

Background: Vaginal discharge [VD] is the most common gynecologic complaint in children. The causes vary from being physiological to sexually transmitted diseases. The anatomy and physiology of the vulva and vagina and the vaginal flora influence the causes to some extent. As the above factors vary as the child grows, the etiology varies too. At any age, VD is responsible for a significant morbidity. Hence enumerating the causes and identifying the common causes in specific age groups will help in development of preventive measures and early appropriate treatment. The aim of the study was to enumerate the cause of VD in children attending the OPD at Government Royapettah Hospital and to find out the causes of VD in specific age groups less than 2 year, 2-9 years and 9-14 years.Methods: A retrospective analysis of twenty girls less than 14 years of age with VD details were collected from the STI cards of twenty children in the age group upto 14 years, with vaginal discharge, who attended the STI clinic at GRH, KMC will be selected and their symptoms, clinical examination findings, results of relevant investigations noted from their hospital records. Children with HIV infection, immunosuppression due to juvenile diabetes mellitus/ malignancy and history of sexual abuse will be excluded. The results tabulated and a descriptive analysis done to find out the most common aetiology in different age groups in children. Descriptive analysis was applied to analyse the results.Results: Out of the twenty children studied 40, 10, 50 percent of the girls were in group A, B and C respectively. Youngest child was 6 months old and oldest was 14 years. In 10% of girls the incidence of VD was physiological and in 90% it was due to pathological causes. In 50% of children the causative agent could be demonstrated by laboratory investigations. Candida was the commonest agent demonstrated in 25% of girls studied. In 35% cases the cause was unidentifiable. Bacterial, parasitic and dermatological causes constituted to 10%, 15%, 10% of aetiology of VD respectively. In one child [5%] who had genital psoriasis, the clinical features of candidal infection was negative.Conclusions: Aetiological diagnosis was very important in children with VD. Not all VD in children are infective and hence anti-fungal and anti-bacterial agents should not be prescribed without adequate clinical and or microbiological evidence. Pin worm infestation should be considered as a cause of VD in girls with perianal excoriation and nocturnal worsening of symptoms.

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AYURVEDIC MANAGEMENT OF ATROPHIC VAGINITIS WITH CERVICAL INTRAEPITHELIAL NEOPLASIA- A CASE REPORT

International Journal of Ayurveda and Pharma Research ◽

10.47070/ijapr.v8i11.1685 ◽

2020 ◽

pp. 69-72

Author(s):

Giby Thomas ◽

Lakshmi Devi.R

Keyword(s):

Case Report ◽

Cervical Intraepithelial Neoplasia ◽

Vaginal Discharge ◽

Symptomatic Relief ◽

Intraepithelial Neoplasia ◽

Burning Sensation ◽

Low Grade ◽

Atrophic Vaginitis ◽

Genital Area ◽

Intraepithelial Lesion

Vaginitis in postmenopausal women is termed as atrophic vaginitis, characterised by vaginal bleeding or spotting, vaginal discharge and discomfort or dryness in vulva. As the symptoms are not usually disclosed by women it may become chronic and can adversely affect the quality of life. In cervical intraepithelial neoplasia the squamous epithelium of cervix is replaced by the cells of varying degree of atypia. Even though CIN1 and CIN2 regress spontaneously, untreated CIN1 and CIN2 lesions may progress to invasive carcinoma. Ayurvedic management for the above conditions focuses on symptomatic relief and improvement of general health and immunity. Oral medication and Sthanika Chikitsa like Kshara Karma and Varthi play vital role in this. A 70 year old lady presented with complaints of burning sensation and itching over genital area. On examination haemorrhagic spots were observed on vaginal walls. She was sent to Early Cancer Detection Centre for cytological screening. The reports showed low grade sqamous intraepithelial lesion. She was managed with oral medications and Sthanika chikitsa. During follow up she was relieved from the symptoms like burning sensation and itching over genital area and vaginal discharge. Bleeding spots on vaginal walls were absent and cytology revealed a negative smear for intraepithelial lesion or malignancy. From this case report it is evidenced that Ayurvedic treatment modality is effective and successful for the management of Atrophic vaginitis with CIN.

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VAGINAL DISCHARGE

The Professional Medical Journal ◽

10.29309/tpmj/2011.18.04.2644 ◽

2011 ◽

Vol 18 (04) ◽

pp. 598-603

Author(s):

SHAHIDA SHAIKH ◽

SALEEM AKHTER SHAIKH ◽

INAYAT MAGSI

Keyword(s):

Vaginal Discharge ◽

Tertiary Care ◽

Care Hospital ◽

College Hospital ◽

Internally Displaced ◽

Syndromic Management ◽

Sexually Transmitted ◽

Medical College ◽

Abnormal Growth ◽

History Of

Objective: To observe the results of syndromic management in women living in IDPs camps complaining of chronic vaginal discharge. Design: Descriptive study. Setting: Medical Camps at Larkana set by Chandka Medical College Hospital for Internally Displaced Persons (IDPs) due to floods. Period: 1st September 2010 to 31st December 2010. Material and Methods: Total 200 symptomatic patients aged from 20 to 50 years suffering from chronic vaginal discharge having history of more than 6 months duration were included in the study. Asymptomatic as well as pregnant women and patients with abnormal cervix and having abnormal growth on cervix were excluded from the study. A detailed history and examination (including speculum and vaginal) was done and a proforma was filled. All these patients were given empirical treatment recommended by WHO as syndromic management consisting of stat doses of antifungal along with antibiotics, where no laboratory tests are required before treatment. Results: Next to vaginal discharge which was main symptom in all patients, the other symptoms like dusparunia, dysuria, itching ,lower abdomen pain and low backache was reported 9%, 16%, 20%, 24% and 31% respectively. Also 8% patients reported post coital bleeding. All patients were married and the mean age of the patients was 28+0.2 years and 15% of them were over 40 years. Mean parity was 4±1.Vaginal infection improved in 65% of the patients excellently with a first line single course of antibiotic and percentage raised up to 88% with second course. 19(9.5%) patients couldn’t be followed as they left that camp and 5(2.5%) patients who did not improve with two courses of antibiotics had big cervical erosions, referred to nearby tertiary care hospital for further management. Conclusions: IDPs live in poor conditions in camps without basic facilities and where it is difficult to perform bedside tests like microscopy, Potassium Hydroxide, wet mount films and tests for Sexually transmitted diseases like Chlamydia and gonorrhea are not available, syndromic management there is a rational way of treating cases of chronic vaginal discharge to get quicker response in such desperate women.

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Estimating and interpreting secondary attack risk: Binomial considered biased

PLoS Computational Biology ◽

10.1371/journal.pcbi.1008601 ◽

2021 ◽

Vol 17 (1) ◽

pp. e1008601

Author(s):

Yushuf Sharker ◽

Eben Kenah

Keyword(s):

Los Angeles ◽

Influenza A ◽

Secondary Infection ◽

Random Variable ◽

Household Member ◽

Primary Case ◽

Multiple Generations ◽

Secondary Infections ◽

Influenza A H1n1 ◽

Binomial Models

The household secondary attack risk (SAR), often called the secondary attack rate or secondary infection risk, is the probability of infectious contact from an infectious household member A to a given household member B, where we define infectious contact to be a contact sufficient to infect B if he or she is susceptible. Estimation of the SAR is an important part of understanding and controlling the transmission of infectious diseases. In practice, it is most often estimated using binomial models such as logistic regression, which implicitly attribute all secondary infections in a household to the primary case. In the simplest case, the number of secondary infections in a household with m susceptibles and a single primary case is modeled as a binomial(m, p) random variable where p is the SAR. Although it has long been understood that transmission within households is not binomial, it is thought that multiple generations of transmission can be neglected safely when p is small. We use probability generating functions and simulations to show that this is a mistake. The proportion of susceptible household members infected can be substantially larger than the SAR even when p is small. As a result, binomial estimates of the SAR are biased upward and their confidence intervals have poor coverage probabilities even if adjusted for clustering. Accurate point and interval estimates of the SAR can be obtained using longitudinal chain binomial models or pairwise survival analysis, which account for multiple generations of transmission within households, the ongoing risk of infection from outside the household, and incomplete follow-up. We illustrate the practical implications of these results in an analysis of household surveillance data collected by the Los Angeles County Department of Public Health during the 2009 influenza A (H1N1) pandemic.

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