Introduction
Visual Impairment
Vision plays a fundamental role in body development because it is primarily source of stimulus that enables direct interaction with the external environment (Pa’dua et al. 2017). Based on American Optometric Association (AOA) in 2007, visual impairment can be defined as a functional limitation of the eye(s) or visual system and can manifest as reduced visual acuity or contrast sensitivity, visual field loss, photophobia, diplopia, visual distortion, visual perceptual difficulties, or any combination of the above. Visual impairment can be the resulted of congenital, hereditary and acquired few conditions. Congenital refers to prenatal or postnatal trauma, genetic or developmental abnormalities, while hereditary could refer to retinitis pigmentosa or Stragardt’s mascular degeneration. Plus, certain acquired condition refers to ocular infection or disease trauma, age-related changes, or systematic disease.
Beforehand, for children with visual impairment often would delay in the developmental process on the domains of fine motor skills and perception. AOA (2007) stated that, children with visual impairment would have a problem in reading standard-sized print, to see chalkboard or whiteboard, overhead projection, or the computer, or to discriminate colors that could lead to the educational and developmental issues. Moreover, children would also face problems in completing daily living task such as doing homework, walking, communicating and socializing. Therefore, indirectly would also affect their self-esteem and level of confidence might be dropped.
Few types of visual impairment which are Albinism, Cataracts, Diabetic Retinopathy, Glaucoma, Age-Related Macular Degeneration (AMD), Retinitis Pigmentosa and Stargardt’s Disease. Albinism is a rare congenital disorder that refers to the pigment deficiency that affected several physical conditions characterized by a lack of hair, skin and eyes pigment. Often people with albinism suffer low vision, photophobia and nystagmus. Next, cataracts are a clouding of the lens of the eye that causes light to be diffused as it enters eye and resulting in a non clarity of a visual image. Cataracts mostly happened due to aging and trauma of the eye.
Diabetic Retinopathy refers to a complication of retinal blood vessels of a person with diabetes, which could cause macular edema. This happened due to elevated of blood sugar levels that damages the blood vessels in the back of the eyes. Individual with diabetic retinopathy having problems such as blur vision, experiencing cloudy vision, loss of color vision, shadows or blind spots. Glaucoma is a damaged happening in the optic nerve that resulting in the unrelieved pressure inside the eye and buildup fluid. Research found that glaucoma is hereditary. Individual with glaucoma might experience frequent headaches, blurred vision, halos around light and difficulty seeing under a dim light.
Age-related Macular Degeneration (AMD) characterized by a worsening and loss of central vision due to the grown of dark spot seen directly in front of the eye and yet the peripheral vision might be clear. This happened a lot among individual in their late 60s. Next, Retinitis Pigmentosa is an inherited eye disease and the symptoms appear during early childhood. This happened due to the degeneration of the retina which specifically the cones and rods. Stargardt’s Disease is a form of macular degeneration that also appears during childhood. Few of the symptoms are blurred and wavy vision, blind spot and impaired of color vision.
Zika Virus Syndrome (ZKVS)
Zika Virus (ZIKV) is a re-emerging arthropod-born virus (arbovirus) in the genus of Flavivirus of the Flaviviridae family, the same family as dengue (DENV), yellow fever (YFV), Japanese encephalitis virus (JEV), and West Nile (WNV) viruses. ZIKV was first discovered during 1940s after it was first identified in a captive rhesus monkey in Zika Forest reserve in Uganda. In the year of 1952, the first human infection of Zika Virus was detected in Uganda. Further notice, in 1966 was the first direct detection of ZIKV outside Africa and the first evidence of transmission by an urban vector, as the virus was isolated form A. Aegypti mosquitoes in Malaysia. Until today, the World Health Organization (WHO) reported a total of 86 countries and territories have evidence on mosquito-transmitted Zika infection.
The infection caused by ZIKV is asymptomatic in most of the cases (Noor & Ahmed, 2018). If the symptoms arise, it would disappear rapidly and based on Noor and Ahmed (2018) reported that, patient did not feel the need of visiting the pathologist since they overview the symptoms as a fever. Some symptoms that reported of person diagnosed with ZIKV included recent onsets of acute fever, malaise, stomachache, dizziness, and anorexia. Based on the World Health Organization (WHO), the symptoms and signs are generally mild including fever, rash, conjunctivitis, muscle and joint pain that usually lasted for two to seven days. The symptoms are often similar with dengue and chikungunya viruses, which is under the family of Flaviviridae. Severity of the infection can lead to death.
Primarily, ZIKV was transmitted via a slyvatic cycle mainly involving the mosquito vector and non-human primates, with human occasionally as a secondary host. Plus, ZIKV also found in many other mammals such elephant, zebras and buffalos. The ZIKV transmitted from a bite of Aedes mosquito and transmitted to other host. Few ways of an individual with ZIKV can transmit its viruses which through perinatal transmission, sexual transmission, and transfusion-associated transmission.
The relationship of ZIKV and visual impairment started to appear after many past research found that there was connection between both of them and have been proved by previous researcher. Even though the main mechanism with ZIKV is that would affect abnormalities and impairment are remained unknown, however the relationship still can be approved. Congenital Zika Syndrome (CZS) is one of the effects of ZIKV infection that later resulted in the microcephaly of infants and fetus during pregnancy phase. Therefore, the main highlights and discussion are much more focuses on the impairment of ZCS within microcephaly that occurs to infants and fetuses and ZIKV infection.
Content
Congenital Zika Virus Syndrome (CZS)
Ventura et. al. (2016) on her research found that numbers of clinical studies had describe the wide spectrum of congenital anomalies and dysfunctions in Congenital Zika Syndrome (CZS). Plus, the finding also includes other abnormalities in multiple neurological such as Gullain-Barre Syndrome, neuropathy and myelitis, few ocular issues, skeletal, and hearing impairments. In addition to that, research reported that there are also additional ocular findings such vascular abnormalities, iris coloboma, lens subluxation, congenital glaucoma and microphthalmia. Again, Ventura et. al. (2016) analyzed the retinal damage by using ocular coherence tomography (OCT), and reported that ZIKV affected in children was due to the severe of retina and choroid that lead to visual impairment in children.
From previous research, it can be stated that there is a strong correlation between ZIKV and visual impairment. Ventura et. al. (2017) stated that after performing a comprehensive ophthalmic and neurologic confirmation for ZIKV infection, reported that many of children with ZIKV infection are likely to have cortical or cerebral visual impairment. Added to that, children with ZIKV infection present an abnormality in visual functional and developmental after being evaluated that likely related to the damage of central nervous system (CNS) and concluded that the main etiology of visual impairment in Congenital Zika Syndrome (CZS) is brain damage.
Congenital Zika Virus Syndrome (CZS) defined as an intrauterine insult mainly, but not only brain, and characterized by arrest of development and even destruction of different portions of the cerebrum and cerebellum (Malinger at. al., 2018). Placenta can be affected through intrauterine infections (IUI), which also would have an impact towards fetus. Mostly, individual diagnosed with ZIKV and giving birth to an infant, an infants would be recognized with the presence of microcephaly, usually severe with small fontanels, narrow sutures, and an abnormal head shape. (Malinger et. al., 2018). However, if an infant were not showing any presence of microcephaly, it would be difficult to suspect the present of CZS and alternatively would be suspected by the presence of abnormal eyes, and limb abnormalities.
According to World Health Organizations (WHO), microcephaly can be defined as a head size is 2 standard deviations (SD) below the mean, based on age and sex as a measurement of head circumference (HC) that also called as accipitofrontal circumference (OFC), is determined by placing a measuring tape within cm and mm scale around the head to include the widest part of the forehead and the most prominent part of the occipital area to arrive at the largest possible measurement (Alvarado-Sacarras et. al., 2018). According to World Health Organization (WHO), this also included the malformations of the head, seizures, swallowing problems, hearing and sight abnormalities.
A significant of increasing cases reported on microcephaly after the outbreak of ZIKV infection in Brazil. The association between ZIKV infection and microcephaly was first suspected in Pernambuco State, Brazil which noted a 20-fold increase in the incidence of microcephaly following the incursion of ZIKV into the country (Bassile et. al., 2017). Congenital Zika virus syndrome (CZS) classified as a collection of abnormalities into a distinct clinical syndrome, comprising structural and functional components. Structural components refer to the cranial morphology, brain anomalies, ocular anomalies and congenital contractures and functional components refer to neurological impairment.
The mechanisms within ZIKV infection that causes CZS that eventually lead to microcephaly is yet remained unknown. de Oliveira Dias et. al. (2018) reported 43 of 51 infants and fetus with brain abnormalities and CZS of microcephaly born with birth defects. Pregnant woman who infected with ZIKV during the first trimester of pregnancy increase the chances of 1-13% cases in the development of brain abnormalities and microcephaly (de Oliveira Dias et. al., 2018). However, in third trimester of pregnancy, the development abnormalities chances are a bit lower since the viruses of ZIKV are having difficulty in passing through layers and membranes of pregnancy autonomy.
Most prominent and commonly reported of clinical feature of CZS suspected is microcephaly. World Health Organization (WHO) has came up with conclusion that Zika virus infection during pregnancy is a cause of congenital brain abnormalities specifically microcephaly. Plus, Zika virus syndrome also can trigger of Guillain-Barré syndrome. Since the increasing of CZS and microcephaly and other neurologic disorder, World Health Organization (WHO) later announced the ZIKV infection as public health emergency started on 1 February 2016 until December 2016.
General features included low birth weight, redundant scalp skin, anasarca, polyhydramnios, and arthrogryposis (Chan et. al. 2016). Ventura et. al. (2016) stated that features in CZS of microcephaly included brain disruption sequence, partially collapsed skull, overlapping cranial sutures, prominent occipital bone, brain abnormalities, hearing impairment and ocular findings. Few techniques are useful to suspect the microcephaly of fetus with CZS like Magnetic Resonance Imaging (MRI), and Ultrasound. Both techniques are detecting the presence of microcephaly during early prenatal phase and fetuses developmental might also be affected.
Visual Impairment within Congenital Zika Syndrome
Based on Ventura et. al. (2018), 119 subjects of infants with Congenital Zika Syndrome were assessed by comprehensive ophthalmic examination, visual function and visual developmental milestones assessment. The findings of infants resulted that 100 of the infants with Congenital Zika Syndrome failed at least one of the milestones test, which compared with five of control infants failed the test. The infants failed to demonstrated both motor and visual development deficits. Therefore, the findings show that infants with CZS also develop in visual impairment.
Visual impairment within CZS is major issues and problems arise and have been focused of many researcher. Since the visual developmental is delayed, other developmental domains also might be affected. As we know that, vision plays major roles in involving daily living task and activities. Therefore, infants might experience many deficiencies during growing up. Children might encounter issues within learning and communication also socialization domains. Therefore, directly would have a large impact on the self-esteem and level of confidence.
Self-esteem of a child might be dropped as growing up with visual impairment. No one wants to live with deficiency and children might shift the blame to their parents after understand the situation his or her are facing. Even though the main causes of visual impairment with Congenital Zika Syndrome (CZS) is brain damage and is something that was not done by the parents, yet the parents would still guilty and sometimes bargaining towards the child condition. Parents also might have a hard time convincing their child to understand and intervene the situation together with the child.
Being left out from peers also can affect the self-esteem and confidence level of child with CZS and visual impairment. They would probably have a hard time fitting themselves in the social norms. Surrounded by peers with impairment might ended up being teased and left out by friends in school. By this, the confidence level might be dropped and socializing can be something impossible for children with visual impairment. Underestimated due to the deficiency often experienced by children with visual impairment, having hard time academically and learning issues might even stress the situation out.
Parents play major roles in finding the best remedies for their child. They roles of finding revenue for the treatment, therapies and other tools needed for children with visual impairment laid down to the shoulder of the father. Meanwhile, mother would often monitor the child developmental along with other siblings. Many issues would arise during the care taking process such as clinical issues, treatment issues and financial issues. However, the parents would still manage the issues to ensure the comfort of child with visual impairment.
Siblings of children with visual impairment might also be affected, since the parents would always focused more on the child with impairment. The parents might spend more expenditure to fulfill the need of child with impairment and the siblings might felt left out and neglected. However, time past and most siblings understood their roles and started to tolerate with the siblings. They will start helping the parents to take care of the child with impairment especially in learning so that the child with impairment can still keep up with the learning syllabus.
The overview of hardship face by family of children with visual impairment was not just stopped right away. Facing new challenges would arise more worrisome to the family. Many factors can be affected from the deficiencies that happened in a family. Relationship, closeness and interaction within family are the major issues that would be encountered by each and every member within a family with a child with an impairment. Some might losing temper, arguments and burst out are all possible. However, intervention and therapy might help the family to understand better and encounter discrepancies in such a good way.
Treatment and Prevention
As technologically developed, is yet to be found of an approved vaccines or specific therapies for ZIKV infection.