Should Prophylaxis Be Given to Close Contacts of A Child with Meningococcal Bacteria in Throat Culture?

Group A Beta-hemolytic Streptococcal Infections

To determine if it is appropriate to recommend that patients with group A beta-hemolytic streptococcal pharyngitis, who are clinically well by the morning after starting antibiotic treatment, can return to school or day care, or if they should wait until they have completed 24 hours of antibiotics as recommended by the American Academy of Pediatrics Committee on Infectious Diseases. We examined the duration of positivity of the throat culture after antibiotics were begun as a means of assessing the potential risk of transmission to close school contacts. Forty-seven children (4 to 17 years of age) with pharyngitis and a positive throat culture for group A streptococci in an outpatient, staff model health maintenance organization clinic were enrolled and were randomly selected to receive therapy with either oral penicillin V, intramuscular benzathine penicillin G, or oral erythromycin estolate. Additional throat cultures were obtained and clinical findings were recorded for each child during three home visits in the 24 hours after their initial clinic visit. Acute and convalescent sera were obtained for determination of anti-streptolysin O and anti-DNase B titers. Seventeen (36.2%) of the 47 patients had a positive culture the morning after initiating antibiotic therapy. However, thirty-nine (83%) of the patients became "culture negative" within the first 24 hours. Neither the time interval to the first negative culture nor the presence or absence of group A streptococcal organisms on any single convalescent culture could be predicted by clinical findings. Six of the eight children who failed to convert to a "negative" throat culture within 24 hours of initiating therapy were receiving erythromycin. We could detect no difference in either time to conversion to a negative culture or the presence of a positive culture 24 hours after starting antibiotics between those who demonstrated a significant antibody increase and those who did not. The data from this study strongly suggest that children with group A beta-hemolytic streptococcal pharyngitis should complete a full 24 hours of antibiotics before returning to school or daycare.

BackgroundDengue fever is an important arboviral disease. The clinical manifestations vary from a mild non-specific febrile syndrome to severe life-threatening illness. The virus can usually be detected in the blood during the early stages of the disease. Dengue virus has also been found in isolated cases in the cerebrospinal fluid, urine, nasopharyngeal sections and saliva. In this report, we describe the isolation of dengue virus from the upper respiratory tract of four confirmed cases of dengue.MethodsWe reviewed all laboratory reports of the isolation of dengue virus from respiratory specimens at the clinical microbiology laboratory of the Kaohsiung Veterans General Hospital during 2007 to 2015. We then examined the medical records of the cases from whom the virus was isolated to determine their demographic characteristics, family contacts, clinical signs and symptoms, course of illness and laboratory findings.ResultsDengue virus was identified in four patients from a nasopharyngeal or throat culture. Two were classified as group A dengue (dengue without warning signs), one as group B (dengue with warning signs) and one as group C (severe dengue). All had respiratory symptoms. Half had family members with similar respiratory symptoms during the period of their illnesses. All of the patients recovered uneventfully.ConclusionsThe isolation of dengue virus from respiratory specimens of patients with cough, rhinorrhea and nasal congestion, although rare, raises the possibility that the virus is capable of transmission by the aerosol route among close contacts. This concept is supported by studies that show that the virus can replicate in cultures of respiratory epithelium and can be transmitted through mucocutaneous exposure to blood from infected patients. However, current evidence is insufficient to prove the hypothesis of transmission through the respiratory route. Further studies will be needed to determine the frequency of respiratory colonization, viable virus titers in respiratory secretions and molecular genetic evidence of transmission among close contacts.

Sudden Cardiac Arrest in an American Indian Infant

To the Editors: P asteurella multocida is a nonmotile, facultative anaerobic, bipolar staining, gram-negative coccobacillus. Humans can become asymptomatic carriers from animal contact and a source of transmission. Few studies have characterized P. multocida strains and confirmed animal and/or human exposure as the direct source of neonatal infection. A 25-day-old infant was admitted with P. multocida (Vitek, bioMérieux, Durham, NC) sepsis and meningitis with positive blood and cerebrospinal fluid cultures. He received a 21-day course of ampicillin (minimal inhibitory concentration < 0.12 μg/mL; Vitek, bioMérieux, Durham, NC) with complete resolution of symptoms during the first week of therapy. On follow-up appointment at 8 months of age, neurologic and developmental assessments were appropriate for his age. Surveillance investigation of close human and animal contacts was performed during the infant’s hospitalization. Throat cultures from the parents and vaginal cultures from the mother were negative for P. multocida. Mouth swabs obtained from both family dogs grew Pasteurella haemolytica. Mouth cultures from an outside cat grew P. multocida. Pulse-field gel electrophoresis (PFGE) and ribotyping analysis were performed at the Infectious Disease Research Laboratory, Christiana Health Care System. DNAs of the isolates recovered from the patient’s CSF and the oral specimens from household pets were digested with SmaI and examined by PFGE. Ribotyping analysis (RiboPrinter System, DuPont Qualicon, Wilmington, DE) of P. multocida strains isolated from the patient and the household cat demonstrated that the strain recovered from the cat was unrelated to the strain isolated from the patients’ cerebrospinal fluid. P. multocida neonatal sepsis and meningitis, although rare, are potentially preventable infections that remain associated with a significant morbidity and mortality in this age group. Most neonatal pasteurellosis cases reported in the English language literature are associated with animal exposure. Nonetheless, only 4 publications used genetic analysis to confirm that the recovered strains from animal contacts were in fact the same P. multocida strains responsible for the neonatal infections.1–4 One study used restriction fragment length polymorphism banding patterns derived from southern blotting and hybridization.3 The other studies used ribotying and/or PFGE to compare 16sRNA gene sequences from reference database with the isolates.1,2,4 Studies that used genetic techniques demonstrated identical strains in the household contacts and the affected infants. In our experience, detailed epidemiologic tracing of his parents and animal contacts failed to recover P. multocida, but in the household cat. DNA analysis by ribotyping and PFGE confirmed that the neonatal infection was caused by a different P. multocida strain, the 1 recovered from the animal. Holst et al5 characterized the clinical manifestations and epidemiology of P. multocida subspecies. In their series of 146 cases, P. multocida subspecies multocida was recovered from the 5 patients presenting with septicemia with or without known animal exposure. Of the 2 isolates recovered from CSF in patients with meningitis, 1 belonged to subspecies multocida and the other to subspecies septica. Animal studies suggest that P. multocida subspecies septica strains might have a greater affinity to cause central nervous system infections.6 Whether certain strains are more likely than others to cause sepsis and meningitis in newborns is unknown. Genetic analysis could assist to characterize the epidemiology and to better understand mechanisms of spread for this infection in neonates. This report emphasizes that DNA fingerprinting of recovered P. multocida isolates must be a requisite to confirm the link between exposure and infection. Andrew S. Wood, MD Department of Pediatrics Bryn Mawr Hospital Bryn Mawr, PA Elyse E. Foraker, BS MT (ASCP) Christiana Care Health Services Wilmington, DE Cecilia Di Pentima, MD, MPH Infectious Diseases Division Department of Pediatrics Vanderbilt University Nashville, TN

We report a case of group C streptococcal meningitis in a woman with a history of close animal contact as well as head trauma as a result of a kick by a horse. Blood and cerebrospinal fluid cultures grew Streptococcus equi subsp. zooepidemicus, as did a throat culture taken from the colt that had kicked her 2 weeks prior to admission.

The annual incidence of acute rheumatic fever (ARF) in Hawaii has remained several times higher than that in the continental United States, particularly among ethnic Polynesians. The emm types of Streptococcus pyogenes that are associated with this nonsuppurative complication have, to our knowledge, not been previously reported in Hawaii. Patients with ARF were identified through an active surveillance system at Kapiolani Medical Center (Honolulu, HI), the only pediatric tertiary care referral hospital in Hawaii. Specimens were obtained by throat culture from patients who met the Jones criteria for ARF at the time of presentation (63 patients), prior to penicillin treatment, and from consenting family contacts (10 individuals). Eight patients and 2 close family contacts with positive throat culture results were identified from February 2000 through December 2005. Group A streptococci isolates were characterized by emm sequence typing. Unusual emm types were temporally associated with the onset of ARF. Emm types 65/69 (from 2 patients), 71, 92, 93, 98, 103, and 122 were isolated from the 8 patients with ARF, and emm types 52 and 101 were isolated from the 2 household contacts. So-called rheumatogenic emm types and/or serotypes, which were previously associated with ARF in the continental United States, were not found in this study. Instead, emm types that are not commonly included among group A streptococci isolates in the continental United States and that are seldom, if ever, temporally associated with ARF were identified. These findings suggest that unusual group A streptococci emm types play a significant role in the epidemiology of ARF in Hawaii.

Acute Poststreptococcal Glomerulonephritis: The Most Common Acute Glomerulonephritis

Coronavirus disease (COVID-19) presents arguably the greatest public health crisis in living memory. One surprising aspect of this pandemic is that children appear to be infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19, far less frequently than adults and, when infected, typically have mild symptoms,1–3 although emerging reports of a novel Kawasaki disease–like multisystem inflammatory syndrome necessitate continued surveillance in pediatric patients.4,5 However, a major question remains unanswered: to what extent are children responsible for SARS-CoV-2 transmission? Resolving this issue is central to making informed public health decisions, ranging from how to safely re-open schools, child care facilities, and summer camps down to the precautions needed to obtain a throat culture in an uncooperative child. To date, few published data are available to help guide these decisions.In this issue of Pediatrics, Posfay-Barbe et al6 report on the dynamics of COVID-19 within families of children with reverse-transcription polymerase chain reaction–confirmed SARS-CoV-2 infection in Geneva, Switzerland. From March 10 to April 10, 2020, all children <16 years of age diagnosed at Geneva University Hospital (N = 40) underwent contact tracing to identify infected household contacts (HHCs). Of 39 evaluable households, in only 3 (8%) was a child the suspected index case, with symptom onset preceding illness in adult HHCs. In all other households, the child developed symptoms after or concurrent with adult HHCs, suggesting that the child was not the source of infection and that children most frequently acquire COVID-19 from adults, rather than transmitting it to them.These findings are consistent with other recently published HHC investigations in China. Of 68 children with confirmed COVID-19 admitted to Qingdao Women’s and Children’s Hospital from January 20 to February 27, 2020, and with complete epidemiological data, 65 (95.59%) patients were HHCs of previously infected adults.7 Of 10 children hospitalized outside Wuhan, China, in only 1 was there possible child to adult transmission, based on symptom chronology.8 Similarly, transmission of SARS-CoV-2 by children outside household settings seems uncommon, although information is limited. In an intriguing study from France, a 9-year-old boy with respiratory symptoms associated with picornavirus, influenza A, and SARS-CoV-2 coinfection was found to have exposed over 80 classmates at 3 schools; no secondary contacts became infected, despite numerous influenza infections within the schools, suggesting an environment conducive to respiratory virus transmission.9 In New South Wales, Australia, 9 students and 9 staff infected with SARS-CoV-2 across 15 schools had close contact with a total of 735 students and 128 staff.10 Only 2 secondary infections were identified, none in adult staff; 1 student in primary school was potentially infected by a staff member, and 1 student in high school was potentially infected via exposure to 2 infected schoolmates.On the basis of these data, SARS-CoV-2 transmission in schools may be less important in community transmission than initially feared. This would be another manner by which SARS-CoV-2 differs drastically from influenza, for which school-based transmission is well recognized as a significant driver of epidemic disease and forms the basis for most evidence regarding school closures as public health strategy.11,12 Although 2 reports are far from definitive, the researchers provide early reassurance that school-based transmission could be a manageable problem, and school closures may not have to be a foregone conclusion, particularly for elementary school–aged children who appear to be at the lowest risk of infection. Additional support comes from mathematical models, which find that school closures alone may be insufficient to halt epidemic spread13 and have modest overall impacts compared with broader, community-wide physical distancing measures.14These data all suggest that children are not significant drivers of the COVID-19 pandemic. It is unclear why documented SARS-CoV-2 transmission from children to other children or adults is so infrequent. In 47 COVID-19–infected German children, nasopharyngeal SARS-CoV-2 viral loads were similar to those in other age groups, raising concern that children could be as infectious as adults.15 Because SARS-CoV-2 infected children are so frequently mildly symptomatic, they may have weaker and less frequent cough, releasing fewer infectious particles into the surrounding environment. Another possibility is that because school closures occurred in most locations along with or before widespread physical distancing orders, most close contacts became limited to households, reducing opportunities for children to become infected in the community and present as index cases.Almost 6 months into the pandemic, accumulating evidence and collective experience argue that children, particularly school-aged children, are far less important drivers of SARS-CoV-2 transmission than adults. Therefore, serious consideration should be paid toward strategies that allow schools to remain open, even during periods of COVID-19 spread. In doing so, we could minimize the potentially profound adverse social, developmental, and health costs that our children will continue to suffer until an effective treatment or vaccine can be developed and distributed or, failing that, until we reach herd immunity.16,17

Urethritis caused by novel Neisseria meningitidis serogroup W in man who has sex with men, Japan.

In Reply.— If patients treated for pharyngitis are symptomatic (with sore throat) at the end of treatment, repeat throat cultures are appropriate. However, if the patient is asymptomatic, routine reculturing is not recommended. The rationale for not performing cultures routinely is that a positive culture from an asymptomatic individual usually identifies a "carrier." Carriers are not thought to be at risk for rheumatic fever, nor are they a source for transmission of the streptococci to their close contacts.

Streptococcal tonsillitis, streptococcal pharyngitis,or streptococcal sore throat (known commonly as strep throat) is a type of pharyngitis caused by a group A streptococcal infection. It affects the pharynx including the tonsils and possibly the larynx. Common symptoms include fever, sore throat, and enlarged lymph nodes. It is the cause of 37% of sore throats among children and 5‐15% in adults.Strep throat is contagious, typically spread via close contact with an infected individual. A preliminary diagnosis is made based on the results of a rapid lateral flow test. A follow up definitive diagnosis is made based on the results of a throat culture. However, these tests are not always needed as diagnosis for administration of treatment may also be made by a physician based on the symptoms.We have previously developed a wireless mobile health application for diagnosis of streptococcal pharyngitis using a smart phone enabled avatar system which uses medical algorithms for diagnosis of this disease, taking advantage of the standard questions and answers typically used by physicians in practice. To further provide confirmation testing of this analysis system, we here describe customization, refinements, and modifications to assay procedures and chemical components of an FDA approved lateral flow rapid diagnostic test for Streptococcal Pharyngitis with a focus on mobile health applications. Specifics of our findings can be applied to other lateral flow assays currently in use for confirmatory tests of other diseases.

Clinical Pearls in Dermatology

Serogroup B meningococcal disease caused 7 US university outbreaks during 2013-2016. Neisseria meningitidis can be transmitted via asymptomatic nasopharyngeal carriage. MenB-FHbp (factor H binding protein), a serogroup B meningococcal (MenB) vaccine, was used to control a college outbreak. We investigated MenB-FHbp impact on meningococcal carriage. Four cross-sectional surveys were conducted in conjunction with MenB-FHbp vaccination campaigns. Questionnaires and oropharyngeal swabs were collected from students. Specimens were evaluated using culture, slide agglutination, real-time polymerase chain reaction (rt-PCR), and whole genome sequencing. Adjusted prevalence ratios (aPRs) were calculated using generalized estimating equations. During each survey, 20%-24% of participants carried any meningococcal bacteria and 4% carried serogroup B by rt-PCR. The outbreak strain (ST-9069) was not detected during the initial survey; 1 student carried ST-9069 in the second and third surveys. No carriage reduction was observed over time or with more MenB-FHbp doses. In total, 615 students participated in multiple surveys: 71% remained noncarriers, 8% cleared carriage, 15% remained carriers, and 7% acquired carriage. Ten students acquired serogroup B carriage: 3 after 1 MenB-FHbp dose, 4 after 2 doses, and 3 after 3 doses. Smoking (aPR, 1.3; 95% confidence interval [CI], 1.1-1.5) and male sex (aPR, 1.3; 95% CI, 1.1-1.5) were associated with increased meningococcal carriage. Carriage prevalence on campus remained stable, suggesting MenB-FHbp does not rapidly reduce meningococcal carriage or prevent serogroup B carriage acquisition. This reinforces the need for high vaccination coverage to protect vaccinated individuals and chemoprophylaxis for close contacts during outbreaks.

The efficacy of rifampin in eradicating Haemophilus influenzae type b from the pharynx of colonized individuals was assessed for 1,467 close contacts of 291 children hospitalized with invasive infections due to H. influenzae type b. Twenty-six percent of all contacts were carrying H. influenzae type b in the pharynx, and 52% of contacts younger than age five had throat cultures positive for this organism. Four different regimens of rifampin were studied and compared with placebo for efficacy in eradication of carriage of H. influenzae type b. The most effective dosage was 20 mg of rifampin/kg given once daily for four days. This schedule was associated with eradication of carriage in 96.2% of 52 colonized, compliant contacts. Carriage of H. influenzae type b was eradicated in 90.9% of the 22 colonized contacts who were younger than age five. Significantly lower rates of carriage eradication were seen with other regimens of rifampin. Potential problems associated with widespread rifampin usage are reviewed.