AbstractObjectiveTo compare the characteristics of suspected measles cases at the health facilities and to determine the representativeness of the data.MethodsWe visited 25 hospitals in the Aniocha Local Government Area (LGA) of Delta State, Nigeria, from which information on reportable diseases was collected. In particular, the suspected measles cases in their registries between January 1, 2007, and June 30, 2008, were reviewed. We compared the characteristics, including age, sex, location, and month of reporting, of the suspected cases with the LGA surveillance records.ResultsIn the LGA records, 10% cases involved individuals older than 14 years, compared with 20% in the same age group in the health facility records. Based on geographic location, 53% of the measles cases among the hospital records came from a single location, in contrast to only 30% of the cases among the LGA records. An analysis considering time revealed that 30% of the cases in the LGA records occurred in August 2007, whereas 20% of hospital cases were reported in February and May 2008 combined.ConclusionsThe two record types differed considerably in all of the characteristics used in this comparison

Fatiregun, Akinola A

Odega, Chuks C

Elsevier - Publisher Connector 

131Asian Pacific Journal of Tropical Medicine (2013)131-134
Document heading          doi:  
Representativeness of suspected measles cases reported in a southern 
district of Nigeria
Akinola A Fatiregun*, Chuks C Odega
College of Medicine, Faculty of Public Health, Department of Epidemiology and Medical Statistics, University of Ibadan, Nigeria
 Contents lists available at ScienceDirect
Asian Pacific Journal of Tropical Medicine
journal homepage:www.elsevier.com/locate/apjtm
ARTICLE INFO                           ABSTRACT
Article history:
Received 10 August 2012
Received in revised form 15 October 2012
Accepted 15 December 2012
Available online 20 February 2013
Keywords:
Representativeness of data
Suspected measles
Surveillance evaluation
Nigeria 
  *Corresponding author: Dr. Akinola A Fatiregun, Department of Epidemiology, 
Medical Statistics and Environmental Health, College of Medicine, University of 
Ibadan, Nigeria.
     Tel: 234 8033720966
     E-mail: fatireguna@gmail.com
1. Introduction
  The importance of a high-quality surveillance system for 
disease control activities has been described extensively[1-3]. 
In September 1998, the World Health Organisation-Regional 
Committee for Africa (WHO/AFRO) adopted the Integrated 
Disease Surveillance and Response (IDSR) strategy to 
strengthen the weak national surveillance and effective 
response to priority communicable diseases in Africa[4]. The 
goal of the IDSR is to improve the ability of the districts, 
called Local Government Areas (LGA), in Nigeria to detect 
and respond to diseases and conditions that cause high 
rates of death, illness, and disability within their catchment 
areas. Nigerian health authorities have since adopted this 
strategy, and the priority diseases, surveillance structure, 
flow of information, monitoring indicators and other details 
have been well articulated[4]. 
  The burden of measles, a highly infectious disease in 
both developing and industrialised nations, has been well 
reported[5,6]. In 2000, the WHO/AFRO adopted a plan to 
reduce the measles mortality in member nations by more 
than 50% before the year 2005[7,8]. The plan included the 
provision of a second opportunity for measles vaccination 
for all children in a wide age range, primarily through 
supplemental immunisation activities, and it also included 
the enhancement of measles surveillance through measles 
case-based surveillance with laboratory confirmation. 
However, the implementation of the plan did not commence 
until December 2005. According to the measles surveillance 
guidelines, any clinician’s diagnosis of measles or illness 
consistent with the case definition of rash, fever and cough, 
coryza, or conjunctivitis should be reported as suspected 
measles. In addition, all patients with suspected measles 
should have blood collected for serologic confirmation[8].
  Since the commencement of the programme in Nigeria, 
large numbers of suspected measles cases have been 
reported and investigated, although the actual number 
of cases in the community is unknown[8,9]. To determine 
the completeness of the reporting of suspected measles 
cases, we conducted a review of suspected measles 
cases in the registries at all health facilities and in the 
Objective: To compare the characteristics of suspected measles cases at the health facilities and 
to determine the representativeness of the data. Methods: We visited 25 hospitals in the Aniocha 
Local Government Area (LGA) of Delta State, Nigeria, from which information on reportable 
diseases was collected. In particular, the suspected measles cases in their registries between 
January 1, 2007, and June 30, 2008, were reviewed. We compared the characteristics, including 
age, sex, location, and month of reporting, of the suspected cases with the LGA surveillance 
records. Results: In the LGA records, 10% cases involved individuals older than 14 years, 
compared with 20% in the same age group in the health facility records. Based on geographic 
location, 53% of the measles cases among the hospital records came from a single location, in 
contrast to only 30% of the cases among the LGA records. An analysis considering time revealed 
that 30% of the cases in the LGA records occurred in August 2007, whereas 20% of hospital cases 
were reported in February and May 2008 combined. Conclusions: The two record types differed 
considerably in all of the characteristics used in this comparison. 
Akinola A Fatiregun et al./Asian Pacific Journal of Tropical Medicine (2013)131-134132
surveillance records at the LGA health department in 
Aniochia LGA of Delta State in southern Nigeria. Using a 
capture-recapture technique, we estimated the reporting 
completeness to be 11.5%[9]. In this report, we compare the 
characteristics of the suspected cases at the health facilities 
with those of the cases reported at the LGA to determine the 
representativeness of the reported data. This measure can 
indicate the quality of the measles case-based surveillance 
system in the LGA.
2. Materials and methods
2.1. Study setting
  The study was conducted in the Aniocha-south LGA of 
Delta State, comprising the Isheagu, Ogwashi-uku, Ejeme-
aniogor, Nsukwa, Ewulu, Umule and Ubulu-okih townships. 
Delta State is one of the 36 States of the Federal Republic of 
Nigeria and is located in the south-south geopolitical zone. 
The Aniocha-south LGA is one of 25 LGAs of Delta State 
with its administrative headquarters in Ogwashi-uku. This 
LGA is geographically located between latitude 6曘11’ and 
6曘15’ north and longitude 6曘25’ and 6曘47’ east[8]. It is 
one of the Igbo-speaking LGAs in the Delta State, with a 
population of 40 605 (2006 census). There are 25 registered 
health facilities, including 2 secondary health care facilities 
and 16 primary health centres, scattered across the LGA. The 
remaining registered health facilities are mission hospitals 
(2) and clinics/hospitals owned by private individuals (3). 
The LGA has a surveillance officer and an assistant, who 
are officials of the LGA health department. Information on 
suspected measles cases is sent to the surveillance office 
from all of the health facilities through the IDSR case-based 
reporting forms[10,11]. 
2.2. Sources of data
  We visited all 25 hospitals in the Aniocha-south LGA of 
Delta State, Nigeria, where the Disease Surveillance and 
Notification (DSN) officers collected information on notifiable 
diseases. We also visited the surveillance office of the 
LGA. The measles cases that were diagnosed in each of the 
health facilities between January 1, 2007, and June 30, 2008, 
were ascertained through a review of the outpatient and 
inpatient registries. Data on the individual cases, including 
age, sex, address, and date of diagnosis, were collected. 
Data on the suspected measles cases that were reported to 
the DSN officer in the LGA during the same period were 
obtained from the LGA office. Ethical clearance to conduct 
the evaluation was obtained from the Delta State Ministry of 
Health Ethics council.
2.3. Representativeness of data
  The characteristics of the measles cases from the health 
facility registries and those from the LGA surveillance office 
were compared in terms of sex distribution, age groupings 
(younger than 5 years, 5-14 years, older than 14 years), 
locations of the cases, and month of diagnosis. The numbers 
of cases in each of these subcategories were represented as a 
proportion of the total number of cases from that source. The 
differences in proportions were evaluated using the Chi-
squared test.
3. Results
 
  Based on a review of the records from the health facilities, 
we identified 15 suspected measles cases with onsets within 
the reviewed period, and we identified 10 cases in the 
surveillance records at the LGA surveillance office. The 
ratios of males to females in the health facility records and 
in the LGA surveillance office were 3:2 and 4:1, respectively 
(P=0.85). When we compared the age distributions of the two 
types of records, we found that 10% of the cases in the LGA 
records involved individuals who were older than 14 years, 
compared with 20% of cases in the health facility records 
(P=0.6) (Figure 1).
60
50
40
30
20
10
0
P
er
ce
nt
ag
e 
of
 to
ta
l c
as
es
 in
 c
at
eg
or
y
LGA records
Hospital records
Under 5 years 5-14 years 斁14 years
Age groups of the meales cases
  
Figure 1. Age distributions of measles cases from the LGA 
records and the hospital records between January 2007 and 
June 2008.
  When we examined the geographic locations of the measles 
cases, we found that four of the seven towns in the LGA had 
cases in the LGA records, with three towns each having 30% 
of the total cases and one other town having the remaining 
Akinola A Fatiregun et al./Asian Pacific Journal of Tropical Medicine (2013)131-134 133
10%. In the hospital records, one town had 53% of the cases, 
and two towns each had 7% (Figure 2).
 
60
50
40
30
20
10
0
P
er
ce
nt
ag
e 
of
 to
ta
l c
as
es
 in
 e
ac
h 
ca
te
go
ry
Ls
he
ag
u
O
gw
as
hi
-u
ku
E
je
m
e-
an
io
go
r
N
su
kw
a
E
w
ul
u
U
m
ut
e
U
bu
lu
-o
ki
ti
LGA record
Hospital record
Locations within the LGA
 
Figure 2. Distributions of measles cases in the LGA and hospital 
records by township between January 2007 and June 2008. 
  Utilising the month of reporting to compare the measles 
records in the hospital surveillance records with those in the 
LGA surveillance records, we found that the health facilities’ 
records showed that 20% of cases occurred in both February 
and May 2008 and that only 6.67% of cases occurred in March 
2007. The LGA records showed that 30% of cases occurred in 
August 2007 and that 10% occurred in February 2007 (Figure 
3).
4. Discussion
  To generalise the findings from the surveillance data to the 
population at large, the data should accurately reflect the 
characteristics of the disease events under surveillance[2].
These characteristics generally constitute time, place and 
person. This study examined the representativeness of 
case-based measles surveillance in the Aniocha LGA of 
Delta State, Nigeria, by reviewing records and comparing 
the frequency and distribution of suspected measles cases 
found in the LGA surveillance record with those found in the 
health facilities’ records. The sensitivity of the LGA measles 
surveillance system during the same period has been 
described previously[9]. In this study, we found differences 
in the distributions of cases based on age, sex, location and 
month of reporting. The importance of these differences 
must be considered in the context of the need for a 
satisfactory surveillance system. The review of health centre 
data found that the percentage of the suspected measles 
cases in persons older than 14 years was 10%, compared with 
20% in the same age group found in the LGA surveillance 
records. This finding contrasts with the finding of a study 
35
30
25
20
15
10
5
0
P
er
ce
nt
ag
e 
of
 to
ta
l c
as
es
 in
 e
ac
h 
ca
te
go
ry
M
ar
-0
7
A
pr
-0
7
M
ay
-0
7
Ju
n-
07
Ju
l-
07
A
ug
-0
7
Se
p-
07
O
ct
-0
7
N
ov
-0
7
D
ec
-0
7
Ja
n-
08
Fe
b-
08
M
ar
-0
8
A
pr
-0
8
M
ay
-0
8
Ju
n-
08
LGA record
Hospital record
Mar-07 Jun-07 Aug-07 Sep-07 Dec-07 Jan-08 Feb-08 Mar-08 May-08 Jun-08
0 0 30 20 20 20 10 0 0 0
6.67 13.33 0 13.33 0 0 20 13.33 20 13.33
Figure 3. Distributions of measles cases in the LGA and hospital records by month of reporting between January 2007 and June 2008.
Akinola A Fatiregun et al./Asian Pacific Journal of Tropical Medicine (2013)131-134134
that examined the reporting efficiency of a measles outbreak 
in New York[12]. The age distributions in the cases recorded 
in the New York City Health Department and those in the 
hospital records were similar[12].
  We found large disparities between the two types of measles 
surveillance records when comparing geographic location 
and time of diagnosis. We found that only one measles case 
could be matched by our matching criteria of name, age, 
sex and location in our estimation of the completeness of 
reporting using the capture-recapture method[9]. This result 
implies that not all cases are being reported and that several 
population subgroups were systematically excluded from 
reporting by the inadequate surveillance system during the 
study period[2].
  This study is limited by several factors, including the 
following: 1) the diagnosis recorded in the clinic registries 
were not confirmed measles cases but were accepted and 
treated as measles cases based on the surveillance case 
definition[13,14], 2) no community-based assessment was 
performed to determine the true incidence of measles in the 
community, and 3) the reliability of the cases documented 
by the health personnel responsible for the records at the 
health facilities may have been limited. Only available 
records could be reviewed.  
  High-quality surveillance data are needed to support 
decision making to control infectious diseases such as 
measles. The differences between the two sets of records 
suggest that some decisions made based on these records 
may not be correct and may slow progress toward achieving 
the goal of effective disease control. More representative 
surveillance data would ensure that the correct population 
or subgroups are targeted for intervention.
Conflict of interest statement
  We declare that we have no conflict of interest.
References
[1]   World Health Organization. Measles situation in Nigeria. [Online] 
Available from: www.who.int/countries/nga/mediacentre/%measles_
background251005.pdf [Accessed on February 2007].
[2]   Centre for Disease Control and Prevention. Updated guidelines 
for evaluating public health surveillance system. [Online]Available 
from: www.cdc.gov. [Accessed on March 2007].
[3]   Jajosky RA, Groseclose SL. Evaluation of reporting timeliness of 
public health surveillance systems for infectious diseases. BMC 
Public Health 2004; 4: 29
[4]   Federal Ministry of Health, Nigeria. National technical guidelines 
for integrated disease surveillance 2002. Nigeria: Federal Ministry 
of Health; 2002.
[5]   Mitchell RJ, Williamson AM, O’Connor R. The development of an 
evaluation framework for injury surveillance systems. BMC Public 
Health 2009; 9: 260.
[6]   Saran R, Hedgeman E, Plantinga L, Burrons NR. Establishing a 
national chronic kidney disease surveillance system for the United 
States. Clin J Am Sc Nephrol 2010; 5: 152-161.
[7]   Centre for Disease Control and Prevention. Measles mortality 
reduction-West Africa 1966-2002. MMWR 2004; 53(2):28-30. 
[8]   Federal Ministry of Health and WHO Nigeria 2006. Guidelines for 
measles surveillance and outbreak investigation, Nigeria. Nigeria: 
Federal Ministry of Health and WHO; 2006.
[9]   Odega CC, Fatiregun AA, Osagbemi GK. Completeness of 
suspected measles reporting in a southern district of Nigeria. 
Public Health 2010; 124(1): 24-27.
[10] Goodson JL, Masresha BG, Wannemuehler K, Uzicanin A, Cochi 
S. Changing epidemiology of measles in Africa. J Infect Dis 2011; 
204: S205-S214.
[11] Weldegebriel GG, Gasasira A, Harvey P, Masresha B, Goodson 
JL, Pate MA, et al. Measles resurgence following a nationwide 
measles vaccination campaign in Nigeria 2005-2008.  J Infect Dis 
2011; 204: S226-S231.
[12] Davies SF, Strebel PM, Atkinson WL, Markowitz LE, Sutter RW, 
Scanlon KS, et al. Reporting efficiency during a measles outbreak 
in New York City, 1991. Am J Public Health 1993; 83(7): 1011-
1015.
[13] Godson JL, Sosler S, Pasi O, Johnson T, Kobella M, Monono 
ME, et al. Impact of measles outbreak response immunization 
campaign: Maroua, Cameroon, 2009. J Infect Dis 2011; 204: 
S252-S259.
[14] Mitiku K, Bedada T, Masresha BG, Kegne W, Nafo-Traore 
F, Tesfaye N, et al. Progress in measles mortality reduction in 
Ethiopia, 2002-2009.  J Infect Dis 2011; 204: S232-S238.


Representativeness of suspected measles cases reported in a southern district of Nigeria 

file:///data/core-remote/dit/data/elsevier/pdf/88c/aHR0cDovL2FwaS5lbHNldmllci5jb20vY29udGVudC9hcnRpY2xlL3BpaS9zMTk5NTc2NDUxMzYwMDA4NQ==.pdf

Representativeness of suspected measles cases reported in a southern district of Nigeria

Abstract

Similar works

Full text

Available Versions

Elsevier - Publisher Connector