Postvaccination Fever Response Rates in Children Derived Using the Fever Coach Mobile App: A Retrospective Observational Study

Abstract

Background Postvaccination fever is a mild adverse event that naturally improves without complications, but is highly prevalent and can be accompanied by febrile convulsions in some cases. These adverse effects may cause parents to delay or avoid vaccinating their children. Objective This study aimed to identify postvaccination fever patterns and the ability of antipyretics to affect changes in these patterns from data collected from a mobile app named Fever Coach. Methods Data provided by parents of feverish children derived from a mobile app, Fever Coach, were used to identify postvaccination fever patterns according to vaccinations and the use of antipyretic drugs. We selected single vaccination records that contained five or more body temperature readings performed within 48 hours of vaccination, and we analyzed postvaccination fever onset, offset, duration, and maximum body temperature. Through observing the postvaccination fever response to vaccination, we identified the effects of antipyretic drugs on postvaccination fever onset, offset, and duration times; the extent of fever; and the rate of decline. We also performed logistic regression analysis to determine demographic variables (age, weight, and sex) involved in relatively high fevers (body temperature ≥39°C). Results The total number of Fever Coach users was 25,037, with 3834 users having entered single vaccination records, including 4448 vaccinations and 55,783 body temperature records. Most records were obtained from children receiving the following vaccinations: pneumococcus (n=2069); Japanese encephalitis (n=911); influenza (n=669); diphtheria, tetanus, and pertussis (n=403); and hepatitis A (n=252). According to the 4448 vaccination records, 3427 (77.05%) children had taken antipyretic drugs, and 3238 (89.15%) children took antibiotics at body temperatures above 38°C. The number of children taking antipyretics at a body temperature of 38°C was more than four times that of those taking antipyretics at 37.9°C (307 vs 67 cases). The number of instances in which this temperature threshold was reached was more than four times greater than the number when the temperature was 37.9°C. A comparative analysis of antipyretic and nonantipyretic cases showed there was no difference in onset time; however, offset and duration times were significantly shorter in nonantipyretic cases than in antipyretic cases (P<.001). In nonantipyretic cases, offset times and duration times were 9.9 and 10.1 hours shorter, respectively, than in antipyretic cases. Body temperatures also decreased faster in nonantipyretic cases. Influenza vaccine-associated fevers lasted relatively longer, whereas pneumococcus vaccine-associated fevers were relatively short-lived. Conclusions These findings suggest that postvaccination fever has its own fever pattern, which is dependent on vaccine type and the presence of antipyretic drugs, and that postvaccination temperature monitoring may ease fever phobia and reduce the unnecessary use of antipyretics in medical care.

Increasing engagement in pharmacology and pharmacogenetics education using games and online resources: The PharmacoloGenius mobile app

“…Among the most important examples, they are currently being investigated as potential tools to enhance adherence during treatment with antiretroviral therapy (Horvath et al, 2019), immunosuppressive medication (Levine, Torabi, Choinski, Rocca, & Graham, 2019) or antipsychotics treatments (Pozza, Coluccia, Gualtieri, & Ferretti, 2020), as well as to enhance commitment during vitamin D intake (Goodman, Morrongiello, & Meckling, 2016) or smoking cessation (Chu, Escobar‐Viera, Matheny, Davis, & Primack, 2019; Pifarre et al, 2017). In the field of pharmacology, mobile applications are currently being tested in pharmacovigilance as a tool to report suspected adverse drug reactions and/or broadcasting safety information (Ahn et al, 2019; Egbring et al, 2016; Pierce et al, 2019). While a large number of mobile applications designed for patients are becoming available, few pharmacology mobile applications directed at students as well as researchers or health care professionals have been developed.…”

Management of acute fever in children: Consensus recommendations for community and primary healthcare providers in sub-Saharan Africa

“… Fever after vaccination is normal and not harmful. Most vaccine-related fevers are detectable 10 to 20 h after vaccination and the duration of fever is usually <12 h [ 109 ]. If an antibiotic is not indicated, explain the reasons why and harms associated with prescribing an antibiotic.…”

“…Fever after vaccination is normal and not harmful. Most vaccine-related fevers are detectable 10 to 20 h after vaccination and the duration of fever is usually <12 h [ 109 ].…”

“…Parents should be warned that fever may occur after vaccination. Time to onset, maximum temperature and duration of fever after vaccination is variable, depending on the type of vaccine [ 109 ]. Administration of antipyretic drugs before or at the time of vaccination, or in the first 6 to 8 h after vaccination, is associated with reduced antibody responses to vaccine antigens [ [110] , [111] , [112] , [113] ].…”

“…Time to onset, maximum temperature and duration of fever after vaccination is variable, depending on the type of vaccine [ 109 ].…”