Human coronaviruses associated with upper respiratory tract infections in three rural areas of Ghana

Abstract

Background: Acute respiratory tract infections (ARI) are the leading cause of morbidity and mortality in developing countries, especially in Africa. This study sought to determine whether human coronaviruses (HCoVs) are associated with upper respiratory tract infections among older children and adults in Ghana.

Methods: We conducted a case control study among older children and adults in three rural areas of Ghana using asymptomatic subjects as controls. Nasal/Nasopharyngeal swabs were tested for Middle East respiratory syndrome coronavirus (MERS-CoV), HCoV-22E, HCoV-OC43, HCoV-NL63 and HCoV-HKU1 using Reverse Transcriptase Real-Time Polymerase Chain Reaction.

Results: Out of 1,213 subjects recruited, 150 (12.4%) were positive for one or more viruses. Of these, single virus detections occurred in 146 subjects (12.0%) and multiple detections occurred in 4 (0.3%). Compared with control subjects, infections with HCoV-229E (OR = 5.15, 95%CI = 2.24-11.78), HCoV-OC43 (OR = 6.16, 95%CI = 1.77-21.65) and combine HCoVs (OR = 2.36, 95%CI = 1.5 = 3.72) were associated with upper respiratory tract infections. HCoVs were found to be seasonally dependent with significant detections in the harmattan season (mainly HCoV-229E) and wet season (mainly HCoV-NL63). A comparison of the obtained sequences resulted in no differences to sequences already published in GenBank.

Conclusion: HCoVs could play significant role in causing upper respiratory tract infections among adults and older children in rural areas of Ghana.

Figure 1. Geographical location of study areas in Ghana.

The study communities are represented by three red dots. The geographic coordinates on the horizontal and vertical regions of the bar show the latitude and longitude coordinates. The red lines show the roads the link the respectively communities.

Figure 2. Virus distribution among age categories of cases and controls.

The x-axis represents the age groups and y-axis shows the number of subjects. Grey bars represent the total number of samples per age group, coloured bars the virus-positive samples. Colour coding is according to virus species as indicated in the legend.

Figure 3. Seasonal distribution and concentration variation of HCoVs.

A: Variation of HCoV-NL63 Concentration. The study areas are represented on the x-axis and the y-axis shows the log10 of HCoV-NL63 concentration in copies per RT-PCR reaction. Data for Kwamang is not shown because of the low numbers detected. Significant differences in viral loads between healthy and control subjects were detected for only the Forikrom community. B: Seasonal distribution of HCoVs. The x-axis shows the various seasons and the “n” value on top of each bar represents the number of subjects recruited in each season. The y-axis shows the percentage of subjects positive for HCoVs.