Multitudes of epidemiological factors contribute to the resultant effects in the mental health of adolescents, defined by the World Health Organization as between ages of 10 to 19. Presently, both prevailing aspects, including the occuring Covid-19 pandemic and the subsequent social lockdown, and inherent social determinants like certain academic environments, poverty, chronic loneliness, and lack of available treatment or research influence the state of adolescent mental health. This literature review seeks to identify critical determinants of adolescent mental health and study their long term influence on mental health epidemiology as a whole. By compiling a plethora of various case studies from publications on PubMed and MEDLINE, APA PsycInfo, and PLOS One along with data from important surveys such as Youth Self Report, Adult Self Report, and TRacking Adolescents’ Individual Lives Survey, this study generates a comprehensive overview of facets underlying the current trends in specifically adolescent mental health. Through the review of critical results extracted from these sources, this paper displays the causal relationship with Covid-19’s social disruptions, especially quarantine, on Vitamin D deficiency and in academic contexts. Furthermore, this paper explores the generalized risk factors associated with mental illness onset in the context of adolescent development along with an evaluation of current trends in mental health research.

Haemophilus influenzae (Hi) can cause meningitis and other serious invasive disease. Encapsulated Hi is classified into six serotypes (a-f) based on chemical composition of the polysaccharide capsule; unencapsulated strains are termed nontypeable Hi (NTHi). Hi serotype b (Hib) was the most common cause of bacterial meningitis in children in the pre-Hib vaccine era, and secondary transmission of Hi among children (e.g., to household contacts and in child care facilities) (1,2) led to the Advisory Committee on Immunization Practices (ACIP) recommendation for antibiotic chemoprophylaxis to prevent Hib disease in certain circumstances.* High Hib vaccination coverage since the 1990s has substantially reduced Hib disease, and other serotypes now account for most Hi-associated invasive disease in the United States (3). Nevertheless, CDC does not currently recommend chemoprophylaxis for contacts of persons with invasive disease caused by serotypes other than Hib and by NTHi (non-b Hi). Given this changing epidemiology, U.S. surveillance data were reviewed to investigate secondary cases of invasive disease caused by Hi. The estimated prevalence of secondary transmission was 0.32% among persons with encapsulated Hi disease (≤60 days of one another) and 0.12% among persons with NTHi disease (≤14 days of one another). Isolates from all Hi case pairs were genetically closely related, and all patients with potential secondary infection had underlying medical conditions. These results strongly suggest that secondary transmission of non-b Hi occurs. Expansion of Hi chemoprophylaxis recommendations might be warranted to control invasive Hi disease in certain populations in the United States, but further analysis is needed to evaluate the potential benefits against the risks, such as increased antibiotic use.

Background

People with HIV (PWH) are at increased risk for invasive pneumococcal disease (IPD). Thirteen-valent pneumococcal conjugate vaccine (PCV13) was recommended for use in US children in 2010 and for PWH aged 19 years or older in 2012. We evaluated the population-level impact of PCV13 on IPD among PWH and non-PWH aged 19 years or older.

Methods

We identified IPD cases from 2008 to 2018 through the Active Bacterial Core surveillance platform. We estimated IPD incidence using the National HIV Surveillance System and US Census Bureau data. We measured percent changes in IPD incidence from 2008 to 2009 to 2017-2018 by HIV status, age group, and vaccine serotype group, including serotypes in recently licensed 15-valent (PCV15) and 20-valent (PCV20) PCVs.

Results

In 2008-2009 and 2017-2018, 8.4% (552/6548) and 8.0% (416/5169) of adult IPD cases were among PWH, respectively. Compared with non-PWH, a larger proportion of IPD cases among PWH were in adults aged 19-64 years (94.7%-97.4% vs. 56.0%-60.1%) and non-Hispanic Black people (62.5%-73.0% vs. 16.7%-19.2%). Overall and PCV13-type IPD incidence in PWH declined by 40.3% (95% confidence interval: -47.7 to -32.3) and 72.5% (95% confidence interval: -78.8 to -65.6), respectively. In 2017-2018, IPD incidence was 16.8 (overall) and 12.6 (PCV13 type) times higher in PWH compared with non-PWH; PCV13, PCV15/non-PCV13, and PCV20/non-PCV15 serotypes comprised 21.5%, 11.2%, and 16.5% of IPD in PWH, respectively.

Conclusions

Despite reductions post-PCV13 introduction, IPD incidence among PWH remained substantially higher than among non-PWH. Higher-valent PCVs provide opportunities to reduce remaining IPD burden in PWH.

Background

Since the introduction of the Haemophilus influenzae serotype b vaccine, H influenzae epidemiology has shifted. In the United States, the largest burden of disease is now in adults aged ≥65 years. However, few data exist on risk factors for disease severity and outcome in this age group.

Methods

A retrospective case-series review of invasive H influenzae infections in patients aged ≥65 years was conducted for hospitalized cases reported to Active Bacterial Core surveillance in 2011.

Results

There were 299 hospitalized cases included in the analysis. The majority of cases were caused by nontypeable H influenzae, and the overall case fatality ratio (CFR) was 19.5%. Three or more underlying conditions were present in 63% of cases; 94% of cases had at least 1. Patients with chronic heart conditions (congestive heart failure, coronary artery disease, and/or atrial fibrillation) (odds ratio [OR], 3.27; 95% confidence interval [CI], 1.65-6.46), patients from private residences (OR, 8.75; 95% CI, 2.13-35.95), and patients who were not resuscitate status (OR, 2.72; 95% CI, 1.31-5.66) were more likely to be admitted to the intensive care unit (ICU). Intensive care unit admission (OR, 3.75; 95% CI, 1.71-8.22) and do not resuscitate status (OR, 12.94; 95% CI, 4.84-34.55) were significantly associated with death.

Conclusions

Within this age group, burden of disease and CFR both increased significantly as age increased. Using ICU admission as a proxy for disease severity, our findings suggest several conditions increased risk of disease severity and patients with severe disease were more likely to die. Further research is needed to determine the most effective approach to prevent H influenzae disease and mortality in older adults.

Objective

Transcripts from admission chest radiographs could aid in identification of pneumonia cases for public health surveillance. We assessed the reliability of radiographic data abstraction and performance of radiographic key terms to identify pneumonia in patients hospitalized with laboratory-confirmed influenza virus infection.

Methods

We used data on patients hospitalized with laboratory-confirmed influenza virus infection from October 2008 through December 2009 from 10 geographically diverse U.S. study sites participating in the Influenza Hospitalization Surveillance Network (FluSurv-NET). Radiographic key terms (i.e., bronchopneumonia, consolidation, infiltrate, airspace density, and pleural effusion) were abstracted from final impressions of chest radiograph reports. We assessed the reliability of radiographic data abstraction by examining the percent agreement and Cohen's k statistic between clinicians and surveillance staff members. Using a composite reference standard for presence or absence of pneumonia based on International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes and discharge summary data, we calculated sensitivity, specificity, positive predictive value (PPV), and percent agreement for individual and combined radiographic key terms.

Results

For each radiographic key term, the percent agreement between clinicians and surveillance staff members ranged from 89.4% to 98.6% and Cohen's k ranged from 0.46 (moderate) to 0.84 (almost perfect). The combination of bronchopneumonia or consolidation or infiltrate or airspace density terms had sensitivity of 66.5%, specificity of 89.2%, PPV of 80.4%, and percent agreement of 80.1%. Adding pleural effusion did not result in significant changes in sensitivity, specificity, PPV, or percent agreement.

Conclusion

Radiographic key terms abstracted by surveillance staff members from final impressions of chest radiograph reports had moderate to almost perfect reliability and could be used to identify pneumonia among patients hospitalized with laboratory-confirmed influenza virus infection. This method can inform pneumonia surveillance and aid in public health response.

BACKGROUND: Respiratory syncytial virus (RSV) is a major cause of hospitalizations in young children. We estimated the burden of community-onset RSV-associated hospitalizations among US children aged <2 years by extrapolating rates of RSV-confirmed hospitalizations in 4 surveillance states and using probabilistic multipliers to adjust for ascertainment biases. METHODS: From October 2014 through April 2015, clinician-ordered RSV tests identified laboratory-confirmed RSV hospitalizations among children aged <2 years at 4 influenza hospitalization surveillance network sites. Surveillance populations were used to estimate age-specific rates of RSV-associated hospitalization, after adjusting for detection probabilities. We extrapolated these rates using US census data. RESULTS: We identified 1554 RSV-associated hospitalizations in children aged <2 years. Of these, 27% were admitted to an intensive care unit, 6% needed mechanical ventilation, and 5 died. Most cases (1047/1554; 67%) had no underlying condition. Adjusted age-specific RSV hospitalization rates per 100 000 population were 1970 (95% confidence interval [CI],1787 to 2177), 897 (95% CI, 761 to 1073), 531 (95% CI, 459 to 624), and 358 (95% CI, 317 to 405) for ages 0-2, 3-5, 6-11, and 12-23 months, respectively. Extrapolating to the US population, an estimated 49 509-59 867 community-onset RSV-associated hospitalizations among children aged <2 years occurred during the 2014-2015 season. CONCLUSIONS: Our findings highlight the importance of RSV as a cause of hospitalization, especially among children aged <2 months. Our approach to estimating RSV-related hospitalizations could be used to provide a US baseline for assessing the impact of future interventions.

The screening method, which employs readily available data, is an inexpensive and quick means of estimating vaccine effectiveness (VE). We compared estimates of effectiveness of heptavalent pneumococcal conjugate vaccine (PCV7) against invasive pneumococcal disease (IPD) using the screening and case-control methods. Cases were children aged 19-35 months with pneumococcus isolated from normally sterile sites residing in Active Bacterial Core surveillance areas in the United States. Case-control VE was estimated for 2001-2004 by comparing the odds of vaccination among cases and community controls. Screening-method VE for 2001-2009 was estimated by comparing the proportion of cases vaccinated to National Immunization Survey-derived coverage among the general population. To evaluate the plausibility of screening-method VE findings, we estimated attack rates among vaccinated and unvaccinated persons. We identified 1,154 children with IPD. Annual population PCV7 coverage with ≥1 dose increased from 38% to 97%. Case-control VE for ≥1 dose was estimated as 75% against all-serotype IPD (annual range: 35-83%) and 91% for PCV7-type IPD (annual range: 65-100%). By the screening method, the overall VE was 86% for ≥1 dose (annual range: -240-70%) against all-serotype IPD and 94% (annual range: 62-97%) against PCV7-type IPD. As cases of PCV7-type IPD declined during 2001-2005, estimated attack rates for all-serotype IPD among vaccinated and unvaccinated individuals became less consistent than what would be expected with the estimated effectiveness of PCV7. The screening method yields estimates of VE that are highly dependent on the time period during which it is used and the choice of outcome. The method should be used cautiously to evaluate VE of PCVs.

Background

Following Haemophilus influenzae serotype b (Hib) conjugate vaccine introduction in the 1980s, Hib disease in young children dramatically decreased, and epidemiology of invasive H. influenzae changed.

Methods

Active surveillance for invasive H. influenzae disease was conducted through Active Bacterial Core surveillance sites. Incidence rates were directly standardized to the age and race distribution of the US population.

Results

During 2009-2015, the estimated mean annual incidence of invasive H. influenzae disease was 1.70 cases per 100000 population. Incidence was highest among adults aged ≥65 years (6.30) and children aged <1 year (8.45); many cases in infants aged <1 year occurred during the first month of life in preterm or low-birth-weight infants. Among children aged <5 years (incidence: 2.84), incidence was substantially higher in American Indian and Alaska Natives AI/AN (15.19) than in all other races (2.62). Overall, 14.5% of cases were fatal; case fatality was highest among adults aged ≥65 years (20%). Nontypeable H. influenzae had the highest incidence (1.22) and case fatality (16%), as compared with Hib (0.03; 4%) and non-b encapsulated serotypes (0.45; 11%). Compared with 2002-2008, the estimated incidence of invasive H. influenzae disease increased by 16%, driven by increases in disease caused by serotype a and nontypeable strains.

Conclusions

Invasive H. influenzae disease has increased, particularly due to nontypeable strains and serotype a. A considerable burden of invasive H. influenzae disease affects the oldest and youngest age groups, particularly AI/AN children. These data can inform prevention strategies, including vaccine development.

Background

The incidence of meningococcal disease is currently at historic lows in the United States; however, incidence remains highest among infants aged <1 year. With routine use of Haemophilus influenzae type b and pneumococcal vaccines in infants and children in the United States, Neisseria meningitidis remains an important cause of bacterial meningitis in young children.

Methods

Data were collected from active, population- and laboratory-based surveillance for N meningitidis conducted through Active Bacterial Core surveillance during 2006 through 2012. Expanded data collection forms were completed for infant cases identified in the surveillance area during 2006 through 2010.

Results

An estimated 113 cases of culture-confirmed meningococcal disease occurred annually among infants aged <1 year in the United States from 2006 through 2012, for an overall incidence of 2.74 per 100,000 infants. Among these cases, an estimated 6 deaths occurred. Serogroup B was responsible for 64%, serogroup C for 12%, and serogroup Y for 16% of infant cases. Based on the expanded data collection forms, a high proportion of infant cases (36/58, 62%) had a smoker in the household and the socioeconomic status of the census tracts where infant meningococcal cases resided was lower compared with the other Active Bacterial Core surveillance areas and the United States as a whole.

Conclusions

The burden of meningococcal disease remains highest in young infants and serogroup B predominates. Vaccines that provide long-term protection early in life have the potential to reduce the burden of meningococcal disease, especially if they provide protection against serogroup B meningococcal disease.

BACKGROUND: Nontypeable Haemophilus influenzae (NTHi) is the most common cause of invasive H. influenzae disease in the United States (US). We evaluated the epidemiology of invasive NTHi disease in the US, including among pregnant women, infants, and people with human immunodeficiency virus (PWH). METHODS: We used data from population- and laboratory-based surveillance for invasive H. influenzae disease conducted in 10 sites to estimate national incidence of NTHi, and to describe epidemiology in women of childbearing age, infants aged ≤30 days (neonates), and PWH living in the surveillance catchment areas. H. influenzae isolates were sent to the Centers for Disease Control and Prevention for species confirmation, serotyping, and whole genome sequencing of select isolates. RESULTS: During 2008-⁠2019, average annual NTHi incidence in the US was 1.3/100 000 population overall, 5.8/100 000 among children aged <1 year, and 10.2/100 000 among adults aged ≥80 years. Among 225 reported neonates with NTHi, 92% had a positive culture within the first week of life and 72% were preterm. NTHi risk was 23 times higher among preterm compared to term neonates, and 5.6 times higher in pregnant/postpartum compared to nonpregnant women. More than half of pregnant women with invasive NTHi had loss of pregnancy postinfection. Incidence among PWH aged ≥13 years was 9.5 cases per 100 000, compared to 1.1 cases per 100 000 for non-PWH (rate ratio, 8.3 [95% confidence interval, 7.1-9.7]; P < .0001). CONCLUSIONS: NTHi causes substantial invasive disease, especially among older adults, pregnant/postpartum women, and neonates. Enhanced surveillance and evaluation of targeted interventions to prevent perinatal NTHi infections may be warranted.